Search

The co-existence of oxygen and nitrogen vacancies in the seaweed-like fibrous membrane is able to complete degradation of antibiotics due to the strengthened ·OH production. [Display omitted] • The seaweed-like fibrous heterojunction membrane with oxygen vacancies in TiO 2 and nitrogen vacancies in g-C 3 N 4 was successfully fabricated through a HCl-mediated strategy. • The thorough elimination of various antibiotics with enhanced reaction kinetics is achieved under visible light irradiation. • The co-existence of oxygen vacancies and nitrogen vacancies are responsible for O 2 capture, H 2 O 2 generation, and ·OH production. • The flexible membrane is also appropriate for flowing systems. The highly selective production of ·OH to strengthen the mineralization of antibiotics remains a significant scientific challenge. In this work, the seaweed-like fibrous membrane containing oxygen-vacancies in TiO 2 ultrafine nanocrystals and nitrogen-vacancies in g-C 3 N 4 nanosheets, was rationally designed through a HCl-mediated polycondensation strategy. The photocatalytic test confirmed that the dual-defects membrane containing dual defects exhibited highly efficient capacities in removing a variety of antibiotics under visible light and natural light irradiation, which was much stronger than that of single- or none-defective samples. The mechanism analysis displayed that the dual defects were beneficial to migration of photogenerated charges, expansion of Fermi level gap, and capture of oxygen. The strengthened ·OH production was derived from the decomposition of H 2 O 2 , bypassing the high barrier of direct oxidation of H 2 O. This work focuses the key roles of defects in photocatalytic reaction and attempts to present a promising stride towards advancing defect engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface C-modified TiO 2 (THF-TiO 2) was prepared using tetrahydrofuran as an additive. • Surface CN-modified TiO 2 (PY-TiO 2) was prepared using pyrrolidine as an additive. • Both THF-TiO 2 and PY-TiO 2 exhibit satisfactory photocatalytic activity and stability. • The C species on the THF-TiO 2 surface enhance the UV photoresponse for the degradation of toluene. • PY-TiO 2 contains surface lattice N, which promotes visible-light harvesting. Surface modified TiO 2 materials are widely used in photocatalytic environmental purification processes. The employment of solution might exert a discernible influence on the catalyst. In this study, we incorporated tetrahydrofuran (THF) and pyrrolidine (PY) during the hydrolysis of titanium butoxide (TBOT) to modify the surface of TiO 2 , successfully synthesizing surface C-modified TiO 2 (THF-TiO 2) and surface CN-modified TiO 2 (PY-TiO 2) catalysts. The assistance of THF and PY not only reduced agglomeration, but also increased the specific surface area of both catalysts, leading to the exposure of more active sites in TiO 2 during the photocatalytic degradation of toluene. When compared to the unsatisfactory degradation of toluene (80%) and CO 2 mineralization efficiencies (40–45 %) observed using unmodified TiO 2 , the synthesized THF-50-TiO 2 and PY-1-TiO 2 microspheres demonstrated enhanced toluene degradation efficiency to 100 % and 99.8 %, respectively, and improved mineralization efficiencies to 76 % and 80 % after 120 min of ultraviolet irradiation. The experimental data and characterization results indicate that the surface-modified carbon species in THF-50-TiO 2 facilitate the acceleration of electron-hole pair separation and suppress recombination. In contrast, partial nitrogen species introduced into the surface lattice of PY-1-TiO 2 narrow its band gap and induce a visible light response. Overall, this study provides two methods to modify the surface of TiO 2 , which can be applied to prepare outstanding photocatalysts for possible application in the degradation of volatile organic compounds (VOCs) present in the air. Furthermore, it has been confirmed that solution have a significant impact on the catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • The TiO 2 films were produced via thermal- and plasma-enhanced atomic layer deposition. • The temperature range of the "PEALD-window" was identified and found to be T = 200–230 °C. • Two distinct ranges of the "TALD-window" were identified: T 1 = 180–220 °C and T 2 = 230–290 °C. • The TiO 2 films produced by PEALD and TALD had an anatase polycrystalline structure. • The crystallinity and optical density of PEALD-TiO 2 is greater than that of TALD-TiO 2. Titanium dioxide thin films were deposited onto single-crystalline silicon wafers using thermal and plasma-enhanced atomic layer deposition (TALD and PEALD) techniques. The TiO 2 films were subjected to investigation via ellipsometry, X-ray diffraction, Raman spectroscopy, and the use of scanning electron and atomic force microscopy techniques. The research findings enabled the identification of the optimal stages' durations of the ALD processes, which ensure the occurrence of saturated surface chemical reactions between the initial components of the film. Furthermore, the "ALD-window" temperature range for implementing the self-limited growth regime to obtain titanium dioxide coatings that are uniform in thickness and homogeneous in composition and structure for PEALD was identified and found to be T = 200 – 230 °C. In the case of TALD, two distinct "TALD-window" ranges were detected. The temperature ranges were determined to be T 1 = 180 – 220 °C and T 2 = 230 – 290 °C. Concurrently, titanium dioxide thin films synthesised by the PEALD may be classified as polycrystalline low-porosity coatings with a surface morphology in the form of extensive "plate-like" domain structures. Conversely, TiO 2 films produced by the TALD method are classified as nano-grained polycrystalline porous coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Constructing CuO@TiO 2 heterojunctions by ALD for enhanced SERS sensitivity. • Systematic optimization of SERS activity by precisely controlling TiO 2 thickness. • TiO 2 coating thickness shows significant impact on PICT processes. • CuO@TiO 2 heterojunctions exhibit exceptional stability and uniformity. Semiconductors hold great promise for surface-enhanced Raman scattering (SERS) applications. Various strategies have been proposed to address the challenge of low SERS sensitivity in semiconductors, with the construction of heterojunctions being among the most effective approaches. In this study, CuO@TiO 2 heterojunctions were fabricated by depositing a precisely controlled layer of TiO 2 film onto the surface of CuO nanowires (CuO NWs) using the atomic layer deposition (ALD) technique. This approach significantly enhances the SERS sensitivity of CuO NWs, and the SERS performance of the semiconductor heterojunction can be further optimized by accurately adjusting the thickness of TiO 2. The SERS activity exhibits systematic variations with the TiO 2 thickness across the CuO@TiO 2 -Rhodamine 6G (R6G) system, with the optimal SERS performance of the heterojunction substrate achieved at a TiO 2 thickness of 250 cycles. This finding highlights the substantial influence of TiO 2 coating thickness on the photo-induced charge transfer (PICT) processes within the CuO@TiO 2 -R6G system. Furthermore, CuO@TiO 2 heterojunctions demonstrate exceptional stability and uniformity. As a result, this study holds significant importance in enhancing the SERS performance of oxide semiconductors, designing optimal semiconductor heterojunction SERS substrates, and investigating thickness-dependent charge transfer mechanisms in semiconductors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanocomposite with TiO 2 NPs encapsulated in MWCNTs internal channels for photocatalyst is fabricated. • The fabrication process is facile and is green, solid chemistry without using a solvent. • Selective growth of anatase crystal phase through heating temperature control. • Successful removal of organic dyes and disinfection of biohazardous substances due to photocatalytic effect. Sustainable energy has been widely researched to address issues caused by population growth and rapid industrialization. Among them, photocatalysis using solar energy has been considered promising. We developed a hybrid photocatalyst by combining titanium dioxide (TiO 2) with carbon nanotubes (CNTs), known for their excellent adsorption performance. A unique structure encapsulating TiO 2 nanoparticles (NPs) within the inner space of multi-walled carbon nanotubes (MWCNTs) was developed via a facile, solvent-free method, conforming to green chemistry principles. Except purification and modification of the CNTs, the particle formation process is solvent-free, making this method remarkably simple and environmentally friendly. This arrangement enhances stability and recyclability, maintaining over 90 % efficiency up to the 3rd cycle. X-ray diffraction (XRD) analysis confirmed that the TiO 2 NPs exhibited a crystalline phase, forming exclusively anatase. The defects in the outer walls of the MWCNTs in the composite, coupled with their large specific surface area and dangling bonds, endow them with high adsorption capacity and photocatalytic activity when combined with TiO 2 NPs. The MWCNTs@TiO 2 composites achieved over 99 % inactivation of Escherichia coli in 60 min and bacteriophage MS2 in 30 min, along with dye adsorption/decomposition. This method offers a distinctive platform for photocatalytic degradation in biological applications and water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bimetallic decorative catalyst with interfacial coupling effect was constructed. • Active Fe 3 O 4 was formed via FePc calcination under air atmosphere. • 97% FDCA yield was obtained at ambient temperature under air oxygen and sunlight. • The mechanism for the synthesis of FDCA was investigated. • This study provides a new strategy for the conversion of HMF to FDCA under mild conditions. The photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is important to facilitate the conversion of biomass into high-value compounds under mild conditions. This study developed Au/TiO 2 catalysts through the urea deposition method, subsequently integrating them with iron phthalocyanine (FePc) via ball milling, resulting in FePc/Au-TiO 2. These catalysts were calcined at various temperatures. The results indicated that Au nanoparticles are uniformly dispersed on TiO 2 , and Fe in FePc/Au TiO 2 calcined at 410 °C mainly exists in the form of ferrosoferric oxide (Fe 3 O 4). FePc/Au-TiO 2 with 30 % FePc which calcined at 410 °C demonstrated outstanding photocatalytic activity, achieving a 97 % yield of FDCA. The effects of various experimental parameters on the conversion of HMF to FDCA were investigated, such as the calcination temperatures, the FePc amount, base, and catalyst dosage. Electron paramagnetic resonance and active species capture tests revealed the catalyst can convert O 2 into •O 2 – and 1O 2 through excited electrons and photogenerated holes. This study highlights the role of interfacial coupling interactions in boosting catalytic performance, offering a novel approach for photocatalyst development in converting HMF to FDCA. [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel one-step reduction gel method is a simple and short-cycle strategy for powders of rutile TiO 2 doped with acceptor ions. • The defects and MA performances were regulated by the introduction of polyvalent copper ions and acceptor ions with a large electronegativity (Ag+ χ = 1.93 > Cu2+ χ = 1.90 > Ti4+ χ = 1.54). • The CT x =0.05 /paraffin composites show an optimum RL min of - 49.8 dB at 2.8 mm and an EAB of 4.20 GHz at 3.0 mm. • The defect complexes ( Ti Ti ′ , V O ∙ ∙ , Cu Ti ″ , Cu Ti ″ ′ , Ti 3 + → V O ∙ ∙ ← Ti 3 + , Ti 3 + → V O ∙ ∙ ← Cu 2 + + e , Cu 2 + + e → Cu + , Ti 4 + + e → Ti 3 + ) bind the electrons to produce stronger polarization relaxation processes. With an increase in electromagnetic (EM) pollution, inducing polarization loss using lattice defects has become one of the main strategies for the design and optimization of a new generation of microwave absorbers. In this study, point defects in TiO 2 absorbers are designed and controlled using a sol–gel method. The influences of the electronegativity difference and the ionic valence states of the dopant ions on the microwave absorption (MA) performance of rutile TiO 2 composites are investigated. The results show that the defects such as oxygen vacancy (V O ∙ ∙ ) and Ti3+ can be adjusted continuously at a high-temperature sintering process. Cu2+, which has a larger electronegativity than Ti4+ (Cu2+ χ = 1.90 > Ti4+ χ = 1.54) promotes the localization of electrons. Furthermore, compared with Ag+, which has a similar electronegativity (Ag+ χ = 1.93 ≈ Cu2+ χ = 1.90), polyvalent copper ions ( Cu 2 + + e → Cu +) enhance the electron-hopping process. The formed electron-pinning defect dipole clusters ( Ti Ti ′ , V O ∙ ∙ , Cu Ti ″ , Cu Ti ″ ′ , Ti 3 + → V O ∙ ∙ ← Ti 3 + , Ti 3 + → V O ∙ ∙ ← Cu 2 + + e , Cu 2 + + e → Cu + , Ti 4 + + e → Ti 3 + ) produce a stronger polarization relaxation process, which regulates the MA performance of TiO 2 absorbers. Therefore, this study provides an essential reference for refining the EM wave attenuation performance of simple oxide absorbers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn-PdPt/TiO 2 with strong metal-MOS interactions was successfully prepared. • Sn-PdPt/TiO 2 sensor exhibited excellent CO and H 2 sensing performance at 200 °C. • The sensitization mechanism of PdPt bimetals on TiO 2 has been proposed. The catalyst with strong metal-support interactions often exhibits high catalytic activity. This study aims to prepare sensitive materials with strong metal-MOS interactions and explore their sensitization mechanism. Sn-PdPt/TiO 2 was obtained by in-situ decorating PdPt bimetals on the surface of TiO 2 NSs using Sn2+ as the reducing agent, and PdPt/TiO 2 was prepared by traditional reduction method. Compared with TiO 2 sensor, PdPt/TiO 2 and Sn-PdPt/TiO 2 sensors exhibited higher sensitivity, selectivity, lower operating temperature (200 °C) and detection limit (ppb level) to CO and H 2. The sensitization of PdPt bimetal to TiO 2 should be ascribed to the high catalytic activity of PdPt bimetal towards O 2 , H 2 and CO, Schottky barrier at the interface between TiO 2 and PdPt NPs, and the multiple valence states (Pd0, Pd2+ and Pd4+) of Pd will undergo mutual transformation during gas sensing reactions. And Sn-PdPt/TiO 2 sensor exhibited higher sensitivity, selectivity and better stability than those of PdPt/TiO 2 sensor, which can be attributed to the introduction of SnO 2 and the stronger interaction between PdPt and TiO 2 due to the in-situ reduction reaction. This study can provide some reference for preparing the MOS based gas sensing materials with strong metal-support interactions and understanding the sensitization mechanism of PdPt bimetal. [ABSTRACT FROM AUTHOR]

[Display omitted] • We show a fast and scalable method for the creation of coral-shaped Ag/TiO 2 nanostrucutres. • Produced structures demonstrate bifunctional SERS and sunlight photocatalytic activity. • Comprehensive analysis explains the TiO 2 nanostructures formation mechanism. Here we propose a fast and scalable (up to 3 min for 6 × 1 cm size substrate) innovative approach to fabricate coral-shaped TiO 2 nanostructured substrates based on thermal oxidation of titanium foil followed by deposition of Ag nanoparticles for bifunctional sensing and photocatalysis. Comprehensive studies on the morphology, crystal structure, stoichiometry, optical, and electronic properties of these nanostructures reveal the formation of a Schottky barrier at the Ag/TiO 2 interface. This interface alters the electronic structure of the Ag/TiO 2 nanosystem, retaining the plasmonic properties of Ag nanoparticles while enhancing their catalytic activity. The SERS performance and photocatalytic activity of Ag/TiO 2 nanostructures are demonstrated by the test analyte Rhodamine 6G detection down to concentrations of 10-12 M and acceleration of its degradation under simulated sunlight by 5.8 times. Tests with tetracycline water solutions indicate a nanomolar detection limit and 4.4-fold increase in degradation rate. The proposed Ag/TiO 2 nanostructures are prospective for creation of low-cost bifunctional platforms for the sensitive detection of organic residues in water as well as their fast neutralization under solar light. [ABSTRACT FROM AUTHOR]

[Display omitted] • Image modes on the anatase TiO 2 (1 0 1) surface were investigated by AFM and DFT, identifying 90% as neutral mode and 10% as protrusion mode. • Tip apex with different terminations clarifies the contribution to neutral and protrusion modes, highlighting the role of tip apex in image mode. • A stable protrusion mode is observed with the Ir-Ti x O y -H tip, show cas ing distinct force interactions at O 2c and Ti 5c sites, essential for understanding surface reactivity. • The study emphasizes the influence of tip-sample charge redistribution on image mode, crucial for elucidating catalytic mechanisms on metal oxide surfaces. The anatase TiO 2 (1 0 1) surface is an important photocatalytic material essential for understanding reactivity and overall materials performance in many applications. We investigate the image modes on the anatase TiO 2 (1 0 1) surface with atomic resolution by AFM at 78 K and density functional theory (DFT) calculations. From the AFM, the image modes are identified as the neutral mode with 90 % and the protrusion mode with 10 %. Through DFT analysis, employing ten different tip-apex terminations, we elucidate these modes: the neutral mode is associated with nine tip-apex terminations, while the protrusion mode corresponds to a single type of termination. Notably, a stable protrusion mode, characterized using the Ir-Ti x O y -H tip apex, indicates the different force curve tendencies at the oxygen (O 2c) and titanium (Ti 5c) sites. Moreover, we found that the neutral mode, observed by the Ir-H tip apex, and the protrusion mode, observed with the Ir-Ti x O y -H tip apex, are significantly influenced by the dipole moments arising from tip-sample charge redistribution, which in turn affects the image mode. The findings reveal essential for elucidating the complex dynamics of image contrast and force interactions for understanding catalytic reactions on metal oxide surfaces. [ABSTRACT FROM AUTHOR]

Caption: Synergistic multi-valence Pd0−Pdδ+ enables superior CO 2 methanation performance with appropriate Pd0/Pdδ+ ratio. [Display omitted] • The Pd-PdO x @TiO 2 model catalysts with tunable Pd0/Pdδ+ ratio are proposed for CO 2 methanation reaction. • H 2 dissociation occurs more efficiently on Pd0 sites, while interfacial Pdδ+ sites mainly dominate CO 2 activation. • The multi-valence Pd0–Pdδ+ synergy governs the adsorption strength of key intermediates. • Pd 21 -Pd 8 O 9 @TiO 2 delivers a superior CO 2 methanation performance to other investigated models. Converting CO 2 waste into valuable chemicals through hydrogenation is promising for reducing atmospheric CO 2 and promoting sustainable carbon recycling. Supported Pd catalysts are commonly studied for CO 2 methanation, yet the pivotal role of interfacial Pd species remains unclear due to ambiguous experimental results, impeding further catalyst enhancements. This study uses theoretical calculations to explore how interfacial Pd sites influence catalytic performance in Pd-PdO x @TiO 2 catalysts during CO 2 methanation. Our findings show that H 2 preferentially dissociates at Pd0 sites, while Pdδ+ sites primarily activate CO 2. Adjusting the Pd0/Pdδ+ ratios optimizes the electronic properties of these sites, enhancing CO 2 activation efficiency. The designed Pd 21 -Pd 8 O 9 @TiO 2 nanocatalyst with adjusted electronic states significantly promotes electron transfer to CO 2 , favoring CH 4 formation by stabilizing the *CH 3 intermediate and reducing the activation barrier for its conversion to *CH 4. These insights advance understanding of interface engineering in metal-support systems for CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow TiO 2 @Fe 2 O 3 Nanofiber were prepared by a simple electrospinning technique. • TiO 2 @Fe 2 O 3 nanofibers were used as functional additive in Lithium sulfur cell. • The Lithium sulfur cell with TiO 2 @Fe 2 O 3 nanofibers demonstrated excellent electrochemical performance. • TiO 2 @Fe 2 O 3 nanofibers promotes capture conversion of polysulfides. High theoretical capacity (1675 mA h g−1) and energy density (2600 Wh kg−1) in addition to low cost, non-toxicity and natural abundance stimulates the exploration of sulfur as a potential cathode material. However, serious capacity fade and poor reaction kinetics leads to untimely failure which prevents the practical commodification of these batteries. Here, a simple and versatile electrospinning technique has been employed to prepare a polymeric template to fabricate hollow metal oxide@metal oxide nanofibers. The hollow fibrous shell with large specific surface area is incorporated as an anchoring material comprising of distinct crystalline phases separated by amorphous domains. Meanwhile, the encapsulated metal oxide nanoparticles ensure efficient conversion of soluble polysulfides thereby, promoting the reaction kinetics and avoiding any surface passivation of anchoring material. The LSB cell with 5 % TiO 2 @Fe 2 O 3 nanofiber additives delivers impressively in the rate capability test with stable capacities of 620 and 480 mA h g−1 at 1C and 2C rate, respectively. Moreover, an excellent cycling performance is attained with a fade rate of 0.092 % per cycle over 500 cycles at 0.5C-rate. The findings of this work shall provide a pathway for facile preparation of functional metal oxide composites for simultaneous trapping and conversion of polysulfide species in sulfur batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • New simple preparation method for metal/semi-conductor thin films. • Structure of TiO2 is investigated for ultrathin films. • Improved photocatalytic properties for multistaked ultra thin films. • Application for plasmonic photocatalysis. The optical and photocatalytic properties of ultrathin TiO 2 layers were investigated in order to stress out the effect of nanoscale thickness on the film properties. The method relies on monitoring localized surface plasmon resonance (LSPR) through UV–visible spectroscopy and enhanced Raman spectroscopy (SERS). To achieve this, TiO 2 thin films were prepared using the sol–gel method on high density gold nanoparticles arrays (AuNPs). TiO 2 anatase phase was obtained by thermal annealing and confirmed by XRD, HRTEM, and SERS. Our results reveal that the thinnest TiO 2 layers consist of compact TiO 2 NPs of small dimensions and lower porosity compared to the thicker TiO 2 NPs layers. Subsequently, these thin TiO 2 layers functionalizing AuNPs were applied in plasmonic photocatalysis, specifically for the N-demethylation of methylene blue in the visible range. When comparing layers with the same thickness (a single deposition layer with layers prepared by stacking various thin layers), the stacked layers demonstrated enhanced photocatalytic activity. This novel, stable form of TiO 2 has the potential to open numerous opportunities in the fields of photocatalysis and detection. [ABSTRACT FROM AUTHOR]

We present a theoretical investigation of the structural, electronic and optical properties of few layer graphene/TiO 2 composites involving either single or bilayer graphene and the (101) surface of TiO 2 anatase, in view of the importance of carbonaceous materials such as graphene to enhance solar light-driven photocatalytic activity of TiO 2. Calculations have been performed by combining periodic DFT calculations to TD-DFT carried out on finite clusters extracted from the periodic structures and embedded in an array of point charges devised to reproduce the periodic electrostatic environment. Although van der Waals interactions dominate the graphene/TiO 2 interaction, TiO 2 properties are significantly affected by its combination with graphene in the composite materials. In particular, we found that such materials present favorable key features for photocatalysis applications, with high charge carriers mobilities, an increase of the absorption in the visible range together with a red-shift of the photoresponse of TiO 2. These results confirm that graphene can enhance solar light-driven photocatalytic activity of TiO 2 , especially when few layer graphene-based composites are considered. Furthermore, the proposed computational approach appears as a reliable and effective tool to model both the electronic and the optical properties of heterostructures at low computational cost. [Display omitted] • A reliable and effective computational protocol is proposed to model composites. • Gr-based composites offer better properties than TiO 2 for photocatalysis. • Few layer Gr-based composites offer better properties than single layer ones. [ABSTRACT FROM AUTHOR]

The adsorption ability of H on the Pd site can be weakened to improve photocatalytic H 2 production by constructing an electron-enriched Pdδ- site. [Display omitted] • An electron-enriched Pdδ- modulation strategy is developed to weaken H adsorption. • The PdAu alloy cocatalyst can markedly enhance the H 2 -evolution performance. • The PdAu/TiO 2 displayed an enhanced H 2 -production activity compared with Pd/TiO 2. Noble metal Pd is a promising H 2 -evolution cocatalyst and has attracted expansive attention in photocatalytic water splitting. However, the present H 2 -production rate of Pd cocatalysts is still limited due to its strong hydrogen adsorption on Pd active sites, resulting in poor hydrogen evolution kinetics. In this work, an electron-enriched Pdδ- modulation strategy is developed to weaken the hydrogen adsorption on Pd active sites by producing PdAu alloy, resulting in an increased H 2 -production rate. In this case, the PdAu homogeneous alloy with a particle size of 9–20 nm is uniformly deposited on the TiO 2 surface to produce PdAu-modified TiO 2 photocatalysts (TiO 2 /PdAu). It is found that the prepared TiO 2 /Pd 79 Au 21 sample achieves the maximal photocatalytic H 2 -production performance of 31.98 mmol g-1 h−1, which is 1.53 times higher than that of TiO 2 /Pd photocatalyst. Experimental and theoretical studies show that in addition to the promoted transfer of photogenerated carriers, the PdAu alloy can spontaneously induce the electron transfer from Au to Pd to form electron-enriched Pdδ- sites, which prominently weakens the Pd-H ads bonds and thus improve the H 2 -production efficiency. This study provides further insight into the rational optimization of active sites to facilitate the design of efficient photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Crystalline TiO 2 and amorphous TiO x homojunction was obtained at room temperature. • OVs played an important role to expand the light absorption range. • Near-perfect lattice-matched TCT can promote the separation of charge. • 73-TCT displayed the dramatically enhanced photocatalytic degradation performance. The light absorption, active sites, and charge carriers separation of photocatalysts are extremely important factors in the field of photocatalysis. Near-perfect lattice-matched homojunction constructed using disorder engineering and doping strategies is an effective strategy to improve photocatalytic activity. Herein, we developed crystalline TiO 2 nanoparticles (NPs) and Ti 3 C 2 T x MXene-derived C-doped amorphous TiO x homojunction (TCT) at room temperature. In this homojunction, TiO 2 NPs are evenly distributed on the surface of the C-TiO x nanosheet to form a type-II structure, which promotes the separation of photogenerated carriers. The light absorption range of TCT extends to 550 nm due to the presence of intermediate energy levels in C-TiO x , which increases its photon absorption capacity. Moreover, TCT possesses a large number of oxygen vacancies, which are beneficial for improving the adsorption and degradation of pollutants. These characteristics of TCT could significantly improve its photodegradation performance for tetracycline. Interestingly, the precursor mass ratio of TCT with the best degradation efficiency is different under different illumination conditions, which is attributed to the different band gaps of C-TiO x and TiO 2 NPs resulting in different light absorption ranges. This work provides a new approach to rationally designing crystalline and amorphous homojunction for photocatalytic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Non-selective hydrophobic aggregation of particles worsened flotation index of ilmenite ore. • WG tended to adsorb onto titanaugite surfaces than ilmenite through physical adsorption. • Selective adsorption of WG only prevented the collector adsorption on titanaugite surfaces. • WG weakened non-selective aggregation of particles by diminishing hydrophobic attraction. • WG had the superior selective dispersion and inhibition in ilmenite flotation. Fine titanaugite readily adhered onto ilmenite surfaces in hydrophobic systems, resulting in a minor difference in floatability. This study utilized sodium silicate (WG) to address these issues. Flotation experiments showed that the serious non-selective hydrophobic aggregation of particles resulted in a low sorting index of a 44.81% TiO 2 grade and a 16.02% TiO 2 recovery when using conventional dispersants in flotation separation of actual ore. However, after utilizing WG, the index of flotation concentrate raised to a 46.50% TiO 2 grade and a 19.84% TiO 2 recovery. Turbidity analysis proved that WG had the strongest destructive impact on the non-selective hydrophobic aggregation between fine titanaugite and ilmenite particles compared to other dispersants. FTIR and XPS analyses verified that WG was inclined to adsorb onto titanaugite surfaces than ilmenite surfaces via physical adsorption. Zeta analysis proved that the selective adsorption of WG prevented the collector adsorption on titanaugite surfaces, while it had little effect on ilmenite surfaces. After adding WG, these changes in reagent adsorptions caused the increase of floatability difference of ilmenite and titanaugite and weakened the heterogeneous hydrophobic aggregation between particles by diminishing hydrophobic attraction. Taken together, WG has superior selective dispersion and inhibition in ilmenite flotation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Algal-assisted nanocomposite for sustainable adsorption of chromium (VI). • Mesoporous TiO 2 @CTAB with a specific surface area was 125.709 m2/g. • The nano adsorbent is cost-effective in the removal of chromium (VI). • The nano adsorbent shows reusability for up to five consecutive cycles. In this study, an investigation of the adsorption efficiency of a novel Spirulina based TiO 2 @CTAB nanoparticle is carried out against one of the highly toxic heavy metal Cr (VI). The co-precipitation method was used to prepare the nanoparticles which were analyzed by various techniques including XRD, UV–Vis spectroscopy, Raman Spectroscopy, FT-IR, BET, FESEM with EDX, Zeta Potential, and Particle Size Analyzer. The pore diameter of the TiO 2 @CTAB nanocomposite was found to be 3.425 nm with a total surface area of 125.709 m2/g. The pH ZPC and XPS studies were used to describe the mechanism of adsorption of Cr (VI) by TiO 2 @CTAB. For synthesized material, the Langmuir adsorption isotherm model exhibits improved adsorption than the Freundlich adsorption isotherm model, having a removal capacity of 127.551 mg/g. The adsorption of CR (VI) on the surface of TiO 2 @CTAB follows pseudo-second-order kinetics having an R2 value of 0.99983. Furthermore, the prepared mesoporous TiO 2 @CTAB adsorbent has high reusability without considerable degradation and may avoid the production of secondary pollutants to a large extent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of Nb content on NiTi SMAs' passivity behavior was studied. • NiTi SMA is susceptible to pitting and crevice corrosion in 3.5 wt% NaCl solution. • Incorporation of Nb 2 O 5 into TiO 2 passive film improves localized resistance. • The addition of 9 at.% Nb makes NiTi SMA immune to localized corrosion. This study explores the passivity and localized corrosion behavior of Ni(100-x)/2Ti(100-x)/2Nbx shape memory alloys (where x = 3, 6, and 9 at.%) through potentiodynamic and potentiostatic polarization tests in 3.5 wt% NaCl solution. The results reveal a significant dependence of the surface passive film's stability on the Nb concentration. Using X-ray photoelectron spectroscopy (XPS), the chemical composition of the passive films formed on the NiTiNb alloys was characterized. Microstructural analysis showed that increasing Nb content affects the volume fraction of the eutectic microconstituent, leading to the suppression of martensite and secondary Ni-Ti phases in the microstructure with higher Nb additions. The findings demonstrate that localized corrosion resistance improves with Nb additions, attributed to the incorporation of Nb 2 O 5 into the TiO 2 passive film, enhancing its protective capacity. Remarkably, the NiTi shape memory alloy exhibits immunity to localized corrosion when 9 at.% Nb is added. [ABSTRACT FROM AUTHOR]

[Display omitted] • The key parameters for electrochemical synthesis of oriented Ag-Ds over TiO 2 nanotubes (TiO 2 -NT) were identified. • Ag-Ds with cavities formed over TiO 2 -NT support were grown at optimized conditions. • Cavity-hosting Ag-Ds deposited over TiO 2 -NT revealed a SERS enhancement factor as high as 109. • The high analytic enhancement factor of the Ag-Ds is associated with the combined effect of chemical enhancement, electromagnetic enhancement, and cavity resonance. Silver nanostructures, utilized as SERS substrates, consistently exhibit exceptional performance in detecting organic compounds through Raman spectroscopy, primarily due to the electromagnetic enhancement mechanism. This study explores an advanced SERS substrate composed of cavities formed by silver dendrites (Ag-Ds) on TiO 2 nanotubes (TiO 2 -NT), demonstrating exceptional performance in detecting organic compounds through Raman spectroscopy. TiO 2 -NT acts as a template, guiding the nucleation and growth of Ag-D to create the cavity structures. The deposition time of silver significantly influences substrate performance in detecting Rhodamine 6G (R6G) and Ibuprofen (IB). It has been observed that an extended deposition time diminishes the enhancement factor. In contrast, a shorter deposition time yields notable enhancement due to the combined effects of electromagnetic and chemical enhancement mechanisms. An optimum deposition time limits dendrite growth, forming cavities where the electric field couples with multiple light reflections, further amplifying the SERS enhancement. The cavity-hosted Ag-D/TiO 2 -NT substrate achieves an impressive analytic SERS enhancement factor of up to 2 × 109, enabling the detection of R6G and IB at a low detection limit of 10-12 M. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pt chemical states could be effectively tuned by H 2 secondary annealing. • Efficient CN/Pt-P25 photocatalyst with high Pt0 ratio was successfully prepared. • It shows excellent naphthalene photodegradation performance (100 % in 100 min). • Improved Pt0 proportion (62.24 %) benefits the separation of photogenerated carriers. Photocatalytic technology holds promising prospects for remediating naphthalene pollution in water bodies. In this work, the CN/Pt-P25 photocatalyst was successfully prepared via photodeposition combined with co-pyrolysis methods, and employed for naphthalene photodegradation under simulated sunlight. The chemical state of Pt was found to have a significant impact on the photocatalytic activity. H 2 secondary annealing effectively tuned Pt chemical states, increasing the proportion of Pt0 species on the CN/Pt-P25 photocatalyst from 41.91 % to 62.24 %. The improved proportion of Pt0 species proportion led to a reduction in the bandgap, which induced changes in the band positions and notably enhancing the separation efficiency of photogenerated electron-hole pairs. Under simulated sunlight irradiation, (H 2) CN/Pt-P25 photocatalyst achieved complete naphthalene photodegradation within 100 min. Thus, photocatalysts containing a high proportion of Pt0 species exhibited an improved performance in naphthalene photodegradation. These findings provide new insights into the application of photocatalytic technology for the remediation of PAHs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient loading of TiO 2 nanoparticles (TiO 2 -NPs) on SPP nanosheets through solid-state dispersion. • Visible-light responsivity enhancement by introducing Ti3+ defects and oxygen vacancies. • Excellent visible-light-driven photocatalytic activity with a 95.6% degradation rate of methylene blue and 187.5 mg · g TiO 2 - 1 · h - 1 degradation efficiency. • Superior recyclability embodied in the retention of 96.4% photocatalytic activity after three regeneration cycles. Ti3+ defective TiO 2 nanoparticles (TiO 2 -NPs) were synthesized through slow hydrolyzation of tetrabutyl titanate and low-temperature annealing, followed by loading on self-pillared pentasil (SPP) zeolite nanosheets to construct a TiO 2 /zeolite hybrid composite by solid-state dispersion. The obtained TiO 2 -NPs/SPP composite exhibited a distinct red-shift in the UV–vis absorption spectrum and a significantly reduced band gap due to the introduced Ti3+ defects and the consequent oxygen vacancies (V O), leading to an enhanced visible-light responsivity. The diverse porosity and house-of-cards nanosheet morphology of the SPP support not only promoted the efficient loading and stable immobilization of TiO 2 -NPs nanoparicles through micropore migration and surface adhesion but also endowed the adsorbability to the TiO 2 -NPs/SPP composite. The adsorptive photodegradation of methylene blue (MB) was used to evaluated the photocatalytic performance of TiO 2 -NPs/SPP, and a 95.6 % degradation rate of MB was observed after 3 h illumination with visible-light. The adsorptive effect strongly promoted the accessibility of MB molecules to the active TiO 2 species, leading to a remarkable enhancement in degradation efficiency. Moreover, a superior recyclability embodied in the retention of 96.4 % photocatalytic activity after three regeneration cycles indicated the TiO 2 -NPs/SPP composite to be practical for water pollutant degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3D core-shell array was constructed on recyclable carbon fiber. • The 3D charge separation interface facilitated efficient carrier separation. • Complete photocatalytic mineralization prevented pollution from toxic byproducts. • The catalyst can be directly recycled without auxiliary equipment. Unsymmetrical dimethylhydrazine (UDMH), as a high-energy liquid rocket fuel widely used for space launches, inevitably produces huge volumes of UDMH wastewater during use. As UDMH and its byproducts are both highly toxic, this poses a major threat to the ecological environment and human body, making it an urgent need to develop an efficient, environmentally friendly treatment for UDMH wastewater. Photocatalysis is well recognized for being less costly and more environmentally friendly, yet as traditional photocatalysts are usually available in the form of powder, the photogenerated carriers cannot be well separated or effectively recycled. In this study, a composite photocatalyst featuring a three-dimensional core-shell array structure consisting of a TiO 2 crystal seed layer, a TiO 2 nanorod array core and a CeO 2 nanoparticle shell is created over the surface of recyclable carbon fiber by means of layer-by-layer loading. The TiO 2 rutile/anatase phase heterointerface and TiO 2 /CeO 2 heterointerface allow efficient separation and migration of photogenerated electrons and holes in the three-dimensional space. Under simulated solar irradiation, our new structure degrades 100 mg/L UDMH wastewater by up to 97.3 % within 240 min. More importantly, it shows good reusability and recyclability. Our research offers a practicable option for the efficient degradation of UDMH wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exfoliation of PTFE magnetic stir bars occurs by friction with TiO 2 nanoparticles. • Fluorinated organic products are formed in the presence of a TiO 2 hybrid material. • Degradation of PTFE bar components is attributed to a synergistic mechanism. • The mechanism may involve friction and ROS formed by hybrid TiO 2. Polytetrafluoroethylene (PTFE) magnetic stir bars are widely used in laboratorial, industrial, and biomedical routine activities due to their chemical inertness. Here the physical exfoliation of PTFE magnetic stir bars, previously revealed in specific experimental conditions, was confirmed in the presence of TiO 2 nanoparticles. Moreover, the chemical surface degradation of PTFE magnetic stir bars was revealed for the first time, due to the effect produced by the oxidative activity of a hybrid TiO 2 -based material under indirect daylight conditions that might be also combined with the tribocatalytic activity of TiO 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • The MoS 2 /BiVO 4 /pre-FTO-MoS 2 /Ni foam PFC was constructed for the first time. • The TiO 2 electron transport layer significantly facilited the charge transfer. • The 2D MoS 2 shortened photogenerated electron migration pathway. • MoS 2 /Ni foam served as the photocathode. • The degradation efficiency was strongly affected by h+ and O2–. The poor contact between the photocatalyst and the FTO substrate are the main factors lead to the low performance of photocatalytic fuel cell (PFC). Herein, a FTO pre-treated with a TiO 2 electron transport layer was used as a substrate for the synthesis of the MoS 2 /BiVO 4 /pre-FTO photoanode. The proposed MBV-4/pre-FTO photoanode with its enhances the visible light absorption and effectively delays the recombination of the photoexcited charge. The MBV-4/pre-FTO composite photoanode (6.02 mA/cm2) exhibited a photocurrent density that was 2.2 times higher than that of the BiVO 4 photoanode (2.78 mA/cm2). This is attributed to the short charge migration length of the thin MoS 2 layer, the fast photoexcited electron transport effect of the TiO 2 seed layer, and the heterojunction structure of the proposed photoanode. The DFT calculation result indicated that the TiO 2 electron transport layer showed an outstanding photoelectron attractive and transporting effect. The MoS 2 /Ni foam was employed as the photocathode to establish a mismatched Fermi level for driving PFC. The short-circuit current, open-circuit voltage, and maximum power density of the PFC were 0.578 mA/cm2, 0.632 V, and 0.125 mW/cm2, respectively. The main photodegradation active species are the superoxide anion (∙O2–) and the photoexcited hole (h+), and the degradation efficiency is 61.97 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced TiO 2 :Gd3+ coatings via PEO with Gd 2 O 3 particles. • The coatings include the Gd 2 O 3 phase in addition to anatase and rutile. • Long time favor the anatase phase while shorter time lead to a higher anatase/rutile ratio. • XPS analysis reveals P and Gd incorporated into TiO₂ network. • Gd and P incorporated in TiO 2 network reduces the band gap from 3.24 to 3.02 eV. • Enhanced photoluminescence intensity and photocatalytic activity in the 3-minute sample. Plasma electrolytic oxidation (PEO) of titanium in 10 g/L Na 3 PO 4 ⋅12H 2 O + 2 g/L Gd 2 O 3 was applied to obtain TiO 2 :Gd3+ coatings. The influence of the duration of PEO on the morphology, chemical and phase composition, absorption and photoluminescence properties of the obtained oxide coatings was investigated and explained in detail. The oxide coatings morphology is dependent on PEO time. The increased PEO time resulted in larger micro-discharge channels, which in turn increased pore size and surface roughness. The elemental components of the PEO coatings include Ti, O, P, and Gd. The oxide coatings are partially crystalline and primarily constituted of TiO 2 phases such as anatase and rutile. Additionally, Gd 2 O 3 , monazite-Gd, and TiO 2 -brookite phases were observed. To represent experimental data, the interactions between TiO 2 , Gd, and P were theoretically investigated using ab initio density functional theory (DFT+U) simulations. The effectiveness of TiO 2 :Gd3+ coatings in photocatalysis was tested by analyzing the photodegradation of methyl orange under simulated sunlight, where the sample TiO 2 :Gd3+ for 3 min of PEO process, shows better photocatalytic performance than the other samples studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface modification methodologies for the bio-functionalization of CPTi are addressed. • Dimensions of surface morphologies spanning from macro-, micro-, to nano-scale. • Anodic treated surfaces granted improved electrochemical resistance. • An upper macroroughness threshold of ≈ 1 µm optimizes fibroblast responses. Titanium is widely used in implants but can cause adverse reactions like inflammation and tissue rejection. Surface modifications like acid-etching and anodization improve implant properties and osseointegration. This study investigated how micro and nanoporous TiO 2 films affect the implant-host interaction, focusing on physical–chemical and biological aspects. Surface treated implants were obtained by acid-etched and anodization of commercially pure titanium (CPTi). Samples were characterized by FE- and FIB-SEM, XRD, EDX, WCA, profilometry, and electrochemical behavior was also investigated. Biocompatibility was accessed by protein adsorption (albumin and serum proteins), hemolysis, and in vitro fibroblast interaction. Anodic samples exhibited the highest corrosion resistance and apatite deposition. Protein adsorption was related to surface roughness and wettability. Samples followed the Langmuir model isotherm (Type I), except for galvanostatic samples (Type III isotherm). Kinetic adsorption was modeled by a pseudo-first-order model, wherein rate-limiting step is albumin diffusion into pores. All surfaces met the hemocompatibility requirements for its use as biomaterial (hemolysis index < 2 %). The upper surface roughness threshold was identified at approximately Sa ≈ 1 µm for better fibroblast viability, adhesion, and proliferation. Combining the results, nanoporous samples present optimized surface conditions that enhance body-fluid contact and improve cell adhesion, thereby contributing to long-term stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2.45 GHz microwave-assisted reactions upgraded TiO 2 /PE into TiO x –TiO 2 /graphene oxide (GO) core/shell nanoparticles within 60 s. • Microwave plasma initiated rapid temperature rise (>600 °C/min) owing to self-heating of surface-modified TiO 2. • High-temperature environment assisted rapid thermal degradation of PE and fast growth of few layer GO. • TiO x –TiO 2 /GO homo/heterojunction exhibited broad light absorption (200–800 nm) and visible-light-driven photocatalytic activity for water purification. • Proposed upgrading-nanotechnology was extended to utilizing various commodity plastics (e.g., PET flakes, PP beads, and PE packs). The efficient formation of hetero-nanostructures remains challenging in various applications. This study demonstrated a fast synthesis of few-layer graphene oxide (GO) uniformly encapsulated with TiO x –TiO 2 nanoparticles by upgrading commercially available TiO 2 powder and commodity plastics (PE, PP, and PET). An application of a 2.45 GHz microwave electric field under vacuum conditions initiated the rapid temperature rise (>600 °C/min) owing to self-heating of the surface-modified TiO 2 with Ti3+/Ti2+ by the plasma etching, followed by the rapid thermal degradation of the plastics and in-situ growth of GO layers on the TiO x –TiO 2 nanoparticles (within 60 s). The TiO x -TiO 2 nanoparticles with GO shells (3–4 layers) demonstrated broad spectrum light absorption (200–800 nm), performing the 3-fold and 6.5-fold higher activity for visible-light-driven photocatalytic degradation of Rhodamine B pollutant than the untreated TiO 2 and the TiO 2 nanoparticles with thick amorous carbon shells, respectively. Moreover, the extended treatment led to the catastrophic destruction of TiO 2 lattice and GO frameworks, resulting in significant activity deterioration (19-fold) despite superior light absorption and further improvement of molecular adsorption capacity. The structurally engineered surface/interface with homo/heterojunction considerably facilitated spatial carrier separation, increasing photocurrent density by more than two orders of magnitude. Upgrading nanotechnology using microwave plasma-initiated reactions would help achieve sustainable development goals. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterojunction materials with hierarchical hollow core–shell structure TiO 2 @Bi-BiOBr was successfully synthesized. • Electron transfer modes at the interface of TiO 2 @Bi-BiOBr composite demonstrated. • The TiO 2 @Bi-BiOBr composite exhibits superior photothermal catalytic CO 2 reduction to CO performance. CO 2 reduction by a sustainable pathway such as photothermal catalysis is highly demanded currently, high carrier recombination rate still severely limits the performance of photothermal catalysis. Constructing heterojunction interfaces with high exposed area is an effective strategy to solve the problem of carrier recombination. However, fine control of the interface structure is still highly challenging. Herein, Density functional theory (DFT) calculations were constructed to reveal that metallic Bi leads to more densities of states (DOS) generation at the conduction band edge in Bi-BiOBr, which argues that photogenerated electrons are more likely to be delivered to metallic Bi. A TiO 2 @Bi-BiOBr hollow hierarchical core–shell heterojunction was designed, providing a highly exposed interface and Bi between interfaces. Such structure endows the catalyst with excellent photothermal catalytic performance, achieving a CO yield of 30.4 μmol·h−1·g−1. The highly improved performance is attributed to interfacial thermoelectrons transfer boosted by the construction of TiO 2 @BiOBr heterojunction as well as metal Bi. And a possible CO 2 reduction pathway is proposed, which is consistent with the Carbine pathway. This study provides an exciting idea for the modulation of photoelectron transfer at catalyst interfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel photocatalyst (D-cys/Au NPs-TiO 2 , DAT) was successfully fabricated. • The highest degradation rate of DAT for chlorpyrifos reaches 96.7%. • The degradation pathway of OPPs involved oxidation of P = S, cleavage of O-P and C-O. • This study provides a potential approach to remove OPPs in fruits and vegetables. The widespread use of organophosphorus pesticides (OPPs) in foods, poses a serious threat to human and environmental health, it is crucial to develop methods that can efficiently degrade residual OPPs. Herein, a chiral TiO 2 photocatalyst was developed by modification TiO 2 with D-cys/Au NPs (DAT) for the simultaneous degradation of four OPPs (chlorpyrifos, chlorpyrifos-methyl, malathion, and parathion) by natural light. The influence of D-Au NPs concentration on the degradation process was optimized, along with the initial pesticide concentration. Under optimal conditions, the photocatalytic degradation efficiencies of DAT for four OPPs were 96.7 %, 56.9 %, 42.6 %, and 49.2 %, respectively, after 12 h of natural light exposure. 12 degradation products of OPPs were identified, among which three products were identified for the first time. The degradation pathway revealed that the degradation of OPPs by DAT involves the oxidation of the P═S bond and the cleavage of the P-O bond and C-O bond. This study establishes a theoretical foundation for applying chiral TiO 2 nanomaterials for the photocatalytic degradation of OPPs in foods. [ABSTRACT FROM AUTHOR]

[Display omitted] • The introduction of potassium bitartrate (KBT) into the TiO 2 film improves TiO 2 surface smoothness and charge transport, reducing recombination centers in PSCs. • KBT in TiO 2 ETLs enhances PSC morphology, reduces interface defects, and improves energy alignment, leading to higher efficiency and stability. • PSCs with KBT show a significant efficiency increase to 23.35 % and maintain over 80 % efficiency after 800 h. The performance of perovskite solar cells (PSCs) has rapidly improved, largely due to advancements in mitigating inherent defects and enhancing interface carrier transport properties. Herein, we provide a facile method to improve the morphology of TiO 2 ETLs, suppress defects at interface, and tailor energy level alignment to enhance carrier separation and extraction efficiency by introducing potassium bitartrate (KBT) into the TiO 2 electron transport layers (ETLs), achieving high-efficiency and stable PSCs. KBT molecules can enhance the surface smoothness of TiO 2 ETLs, resulting in denser and more uniform perovskite films. In addition, the carboxyl groups, hydroxyl groups, and potassium cations containing in KBT improve charge transport efficiency at TiO 2 /perovskite interface by reducing non-radiative recombination centers in TiO 2 and perovskite bottom as well as improving energy level matching. As a result, the target PSC exhibits an obvious improvement in performance with a champion efficiency of 23.35 %, which is greatly improved relative to the control (21.66 %). The long-term operational stability is also remarkably enhanced, after 800 h MPPT, PSCs with KBT remain over 80 % of its initial efficiency. PSCs with KBT-doped ETLs exhibit increased efficiency and stability, highlighting potential of KBT as an interface engineering tool for enhancing PSCs performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pt modified OMT surface is successfully synthesized via EISA process. • Our sensor shows excellent humidity sensing performance and long-term stability. • 5 % Pt-doped OMT sensor exhibits high response S R ∼ 3.9 × 105 toward 95 % RH. • Fast response time (26 s) is observed for 5 % Pt-doped OMT with excellent repeatability. • Our sensors outperform commercial counterparts in response and recovery time. Platinum modified ordered mesopore TiO 2 (OMT:X Pt) with tunable channel was synthesized via soft-templet method known as Evaporation Induced Self-Assembly (EISA). Both porosity and metal doping have a significant impact on how metal oxide semiconductors respond to humidity. Thus, based on earlier studies, Pt-doped ordered mesoporous TiO 2 was synthesized and described under optimal conditions. From nitrogen adsorption and desorption analysis, while it was found that the specific surface area decreased (from 240 to 125 m2/g), pore size increased (from 4 to13 nm). The humidity sensing performance of the Pt-modified OMT is investigated by dynamic sensing system. The sensor based on 5 wt% Pt-doped OMT showed high response (SR ∼ 105), fast response time (26 s) to 95 % relative humidity (RH) and good long-term stability (over 90 days). To understand and authenticate the sensing mechanism, the structure and morphology of synthesized Pt-doped OMT was performed by BET, SEM, HRTEM, XRD and XPS. Furthermore, a plausible sensing mechanism is discussed on basis of the obtained results. [ABSTRACT FROM AUTHOR]

[Display omitted] • WB 5-x as efficient cocatalyst for photocatalytic applications is proposed. • 5 wt% WB 5-x -WB 2 /TiO 2 possesses 23 times higher H 2 production rate than TiO 2 (81 H 2 µmol h−1 g cat –1) • 10 wt% WB 5-x -WB 2 /TiO 2 shows 4 times higher CO 2 RR rate than TiO 2 (108 µmol h−1 g cat –1) • New application direction for transition metal borides in photocatalysis is proposed. Catalytic reactions play an important role in modern industry as almost 90 % of the chemical industry is based on catalytic reactions. The development of new, more efficient catalysts will allow significant advances in chemical production, but still remains a rather challenging problem for materials scientists. Here, we have proposed and investigated a new composite photocatalyst based on WB 5-x -WB 2 and TiO 2 for H 2 evolution from aqueous ethanol solution and CO 2 reduction under visible light irradiation (410 nm). New composite photocatalysts WB 5-x -WB 2 /TiO 2 were synthesized and characterized by X-ray diffraction, UV–vis spectroscopy, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Photocatalytic measurements show that the maximum activity of the composite photocatalyst 4 and 23 times higher than the activity of unmodified TiO 2 in CO 2 reduction and H 2 evolution, respectively. Density functional calculations of the proposed reaction are in agreement with the provided experiments confirming the higher efficiency of the modified catalyst compared to TiO 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • The refractory high entropy has been successfully synthesized by DGPSA technology. • The microstructure of the coatings exhibited BCC solid solution phase. • The highest hardness of Ta 37.5 Cr 45.9 Ti 8.5 Zr 4.8 W 2.5 coatings can reach 1967 HV 0.5N. • A complex protective oxide layer was generated on the coatings surface. • The addition of Zr accelerated the rapid formation of Cr 2 O 3. The high-temperature oxidation behaviors of a series of refractory high entropy alloys TaCrTiW and TaCrTiZrW alloy coatings at 1073 K in air were studied. A complex protective oxide layer consisting of Cr 2 O 3 , TiO 2 , and CrTaO 4 oxides was generated on the alloys surface. Among the TaCrTiW alloy coatings, the presence of TiO 2 inhibited the generation of unfavorable oxides and promoted the generation of CrTaO 4. The Ta 41.7 Cr 50.3 Ti 4.5 Zr 1.6 W 1.9 exhibits excellent oxidation resistance. The addition of Zr not only accelerated the initial oxide formation but also promoted the rapid formation of Cr 2 O 3. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVDF-based photocatalytic films were prepared by ink-jet printing. • TiO 2 @CQDs heterostructures were immobilized on the film surface. • The effective charge transfer interface of TiO 2 (i)@CQDs led to a high η at low loading. • The ks of PVDF/TiO 2 (i)@CQDs was improved by about 4.3 times. • The small and uniform catalyst improved photoactivity and prevented nozzle clogging. PVDF/TiO 2 @CQDs hybrid photocatalytic thin films were prepared by ink-jet printing. The printing ink was prepared with the TiO 2 , TiO 2 (s)@CQDs (surface composite), and TiO 2 (i)@CQDs (situ doping) nanoparticles as precursors, respectively. Compared to TiO 2 (s)@CQDs, TiO 2 (i)@CQDs has a smaller particle size (about 10.01 nm) and a narrower particle size distribution (6∼14 nm), which can improve the photocatalytic effect while avoiding nozzle clogging. The PVDF/TiO 2 (i)@CQDs hybrid film exhibited a high degradation efficiency (η) of 93.71 % for Rhodamine B (RhB) within 150 min under visible light with a catalyst load of only 0.49 wt%. The reaction rate constant (ks) of the PVDF/TiO 2 (i)@CQDs film was about 4.3 times higher than that of the PVDF/TiO 2 (s)@CQDs film. The small particle size of this S-scheme TiO 2 (i)@CQDs heterostructure nanoparticle and the more effective contact interface formed between TiO 2 and carbon quantum dots (CQDs) further facilitated electron transfer and enhanced photoactivity. The firmly immobilized catalysts on the Polyvinylidene fluoride (PVDF) film substrate through Ti-F coordination bonds ensured the reusability and stability of the photocatalytic film (the η of RhB still reached 88.05 % after 10 consecutive cycles). This work provides a new strategy for the application of ink-jet printing technology in photocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photoelectrochemical-electrostatic co-sense is realized with black phosphorus. • Multivariate van der Waals heterojunctions are used to engineer material defects. • Response can be promoted to 236.4 μA cm−2 stimulated by AEF combined with light. • Response is 1.8 and 19.4 times higher than that stimulated by AEF or light alone. Nowadays, the two-dimensional (2D) materials have shown broad prospects for their fascinating attributes, yet the ineluctable material defects still restrict their applications. Herein, a spin-coating technology is employed to establish few-layers borophene/bismuthene/Ti 3 C 2 T x MXene/black phosphorus (BP) laminations, and then a photoelectrochemical-electrostatic coupling sensor is developed. It is demonstrated that the rough defects on the Si/Ag substrate can be patched by the upper few-layers borophene and bismuthene, and the residual defects on the Ti 3 C 2 T x layer can be exactly patched by the as-derived TiO 2 and the upper 2D BP layers. These 2D metals have been bounded with adjacent 2D semiconductors through van der Waals interactions to greatly depress the metal-induced gap states and enhance the carrier transport. Under just light irradiation or ambient electric field (AEF), the current response of the lamination electrode obviously increases, compared to that without the key BP cover layer. Further, the response can be promoted to 236.4 μA cm−2, stimulated by AEF combined with light irradiation, which is about 1.8 times and 19.4 times higher than that of light irradiation alone and AEF alone, respectively. These can be attributed to the defect engineering effect, by which the 2D materials constantly mending the defects. [ABSTRACT FROM AUTHOR]

[Display omitted] • The method of SF 6 degradation by DBD cooperating with photocatalysis is proposed. • Demonstrate the synergistic effect between TiO 2 photocatalysis and DBD. • Pre-adsorption of H 2 O enhanced the bond breaking and reduced the energy barrier. • Active sites exhibited strong adsorption of crucial intermediates. • Elucidated the evolutionary mechanism of the SF 6 degradation and conversion pathway. Research into the degradation and conversion of SF 6 is important for environmental protection. Dielectric barrier discharge (DBD) technology is recognized as a reliable method for processing industrial waste gases, such as SF 6. This research introduces a dual approach, combining DBD with TiO 2 photocatalysis, to enhance SF 6 degradation. When operating at 90 W, the degradation removal efficiency (DRE) of 2 % SF 6 reaches 99.99 %. Moreover, the energy efficiency, measured as G50, reaches 10.25 g/(kW·h) for the combined DBD and TiO 2 photocatalysis system, is, surpassing the efficiency of the standalone DBD system. The introduction of 0.5 % H 2 O enables complete SF 6 degradation at a reduced input power (70 W). This synergy promotes the generation of a more easily processed product, SO 2. Density functional theory (DFT) studies indicate that the availability of active sites on TiO 2 (1 0 1) is a crucial factor affecting the degradation efficiency. Specifically, the pre-adsorption of H 2 O on TiO 2 (1 0 1) surfaces facilitates the initial bond dissociation of SF 6 , while these surfaces strongly adsorb crucial intermediates, thereby enhancing the degradation of SF 6. Additionally, the selectivity of the products was related to the dissociation energy barriers, and the pre-adsorption of H 2 O reduces these barriers for key intermediates, thereby improving SO 2 selectivity. This study provides new insights into SF 6 degradation and conversion using DBD combined with photocatalysis and provides inspiration for the conversion of other greenhouse gases (CO 2 , CH 4 , etc.). [ABSTRACT FROM AUTHOR]

[Display omitted] • The Dual oxide co-decorated necklace-like CNF (TiO 2 @SiO 2 /CNF) flexible electrocatalytic membrane interlayer was prepared. • The necklace-like structure enhances structural stability and provides more active sites. • The TiO 2 @SiO 2 /CNF synergistically combined the advantages of high conductivity and high electrocatalytic activity. • The Li-S batteries with TiO 2 @SiO 2 /CNF interlayer achieve outstanding rate performance and cycling stability. Lithium-sulfur (Li-S) batteries are regarded as new energy storage systems due to their low cost and high specific energy density; however, their commercial prospects are hindered by the shuttle effect of lithium polysulfides (LiPSs). Herein, the fabricating necklace-like carbon nanofibers membrane co-decorated by TiO 2 and SiO 2 (TiO 2 @SiO 2 /CNF) is prepared by the electrospinning technique as an interlayer to catalyze the conversion of LiPSs in Li-S batteries. The necklace-like nanofibers provide a three-dimensional conductive network, enabling SiO 2 synergy with TiO 2 to accelerate the redox kinetics of LiPSs through an enhanced interfacial effect. The Li-S batteries based on TiO 2 @SiO 2 /CNF interlayers exhibit an impressive specific capacity of 658 mAh g−1 at 3.0C, and their performances are decayed only 0.05 % per cycle at 1.0C within 500cycles. Our study reveals that the shuttle effect addition of LiPSs can be significantly improved by rational structural design, thus enhancing the electrochemical performance of Li-S batteries. The synthesis of necklace-like TiO 2 @SiO 2 /CNF presents a promising strategy for designing functional interlayers for advanced Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-TiO 2 /Ti 3 C 2 T x was constructed via a facile in-situ oxidation and calcination. • P-doped TiO 2 /Ti 3 C 2 T x improved the kinetics of the Li-O 2 battery reaction. • P-TiO 2 /Ti 3 C 2 T x with local active site optimization facilitated the LiO x conversion. • P-doped TiO 2 /Ti 3 C 2 T x generates the unique nanosheets array discharge product Li 2 O 2. The performance of Li-O 2 batteries is seriously limited by the sluggish kinetics of the mass transition in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). To explore a useful strategy to overcome these limitations, herein, we constructed a P-doped TiO 2 /Ti 3 C 2 T x heterostructure (PTT) with local active site optimization, in which the highly conductive substrate anchored the P-TiO 2 nanoparticles with a selective adsorption and conversion of LiO x. In contrast to the TiO 2 /Ti 3 C 2 T x heterostructure with a relatively uniform active site inducing typical toroidal Li 2 O 2 , the introduction of P-doping generates a unique nanosheet array Li 2 O 2 on the PTT surface as a discharge product. This unique structure is endowed with a shorter Li+ diffusion path and benefits mass transfer in ORR and OER, facilitating the reaction kinetics. It presents obviously enhanced battery performance with a high specific capacity of 13,482 mAh g−1 and decreased discharge–charge overpotential, as well as superior cycling stability of 190 cycles. Furthermore, this novel and efficient electrocatalyst can stably operate for more than 650 cycles at 1000 mA g−1 with the addition of a LiI redox mediator. This study provides new insight into high-performance electrocatalyst design in Li 2 O 2 related battery system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Formation of Laser Induced Periodic Surface Structure (LIPSS) on TiO 2 surface upon irradiation with femtosecond-UV laser. • Observation of two different systems of low spatial frequency LIPSS. • Pulse-by-pulse transition from high to low spatial frequency LIPSS. • Proposal of a mechanism to explain the role of the HSFL in the formation of the LSFL. • Numerical simulations supporting the evolution from HSFL to LSFL with increasing the number of laser pulses. The formation of laser-induced periodic surface structures (LIPSS) on a TiO 2 (0 0 1) oriented surface upon irradiation with UV-fs laser pulses was analyzed. Two systems of low spatial frequency LIPSS (LSFL) perpendicular to the direction of laser polarization are observed after N = 5 laser pulses. One was developed on the edges of the crater created by the first laser pulse, while the other appeared in the center of crater and spread towards the edges. When N was greater than 10, the two LIPSS systems merge. Both LSFL systems have a spatial period of approximately 200 nm and are due to the coherent superposition of surface waves scattered on inhomogeneities of a transient metallic surface. However they differ by the type of defects involved in the excitation process of surface waves. While a pronounced and localized rim triggered LSFL on the edge of the laser spot, LSFL in the central part nucleated at the shallow high spatial frequency LIPSS (HSFL), which are parallel to the laser polarization. A mechanism is proposed to explain the role of the HSFL in the formation of LSFL. Numerical simulations of the absorbed laser power density support the evolution from HSFL to LSFL as the number of laser pulses increased. [ABSTRACT FROM AUTHOR]

[Display omitted] • The new TiO 2 /Au/PMMA structure achieves high hardness and excellent transparency. • Robust electromagnetic interference shielding efficiency within the range of 19–29 dB. • The function lead to applications for aerospace equipment and visualization windows. This research addresses the critical need for a highly stable and transparent electromagnetic shielding coating for aircraft PMMA windows and canopies, crucial for safeguarding against electromagnetic interference and enhancing aircraft stealth capabilities. The study presents the novel design, deposition and investigation of transparent coatings, specifically TiO 2 /Au, on PMMA organic glass cockpit canopies. Optimization of TiO 2 and Au film thicknesses is achieved through simulation using TFcalc software, incorporating polarization and optical constants data obtained in this study. The experiments reveal that the deposition of TiO 2 /Au/TiO 2 on PMMA results in fogging, reducing transparency, while novel TiO 2 /Au coating does not exhibit this issue. The TiO 2 /Au configuration, featuring a TiO 2 layer approximately 30 nm thick and an Au film ranging from 11 to 15 nm in thickness, demonstrates outstanding attributes, including a remarkable transparency level of approximately 70–80% and robust electromagnetic interference shielding efficiency within the range of 19–29 dB across S, C, X, and Ku bands of electromagnetic waves. These exceptional performance characteristics position it as an ideal choice for aviation applications. The synergy of the stable Au and durable TiO 2 components, with their high hardness and self-cleaning properties, extends its potential utility to a diverse array of applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A one-step synthesis of bi-element gradient doped TiO 2 with B/N non-uniform distribution. • Boron tends to be surface doped while nitrogen intervenes at deeper positions. • Ti3+/O v defects and positive charge surface in the B/N-TiO 2-x are formed due to Ti-B bonding. • High catalytic performance is reflected in the treatment of g/L level Cr(VI). • The interfacial catalytic properties of the composites are highly Boron dose-dependence. Studying the influence of non-uniform distribution of bi-element doping on the surface structure and photocatalytic performance of TiO 2 in interface photocatalytic processes can be an interesting research topic. Taking B/N bi-element doped TiO 2 as an example, this article reports an extremely simple gradient doping method of TiO 2 and its enhancement mechanism for high concentration wastewater treatment. The surface enrichment and doping of B caused by electrostatic and atomic radius factors changed the charge properties of the complex during the induction of in-situ reduction of Ti4+. The defects in gap N and Ti3+ lead to the formation of intermediate states, resulting in a narrowing of the band gap of the composite to 2.58 eV. The gradient doping of two atoms endows the optimal photocatalyst with a larger specific surface area (114 m2∙g), stronger photocurrent response (0.179 mA·cm−2), suitable Ti3+/O v double defect structure, and surface positive charge properties. These characteristics improve the effective treatment of high-concentration pollutants by the preferred B 2 /N-TiO 2-x [ e.g. , 0.0059 min−1 for 0.5 g·L-1 Cr(VI)] and sustainable treatment (removal efficiency > 90 % within 5 cycles). The synthesis strategy will provide a fast, simple, and safe method for the design and synthesis of new TiO 2 based catalysts in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ru/TiO 2 /Al 2 O 3 catalysts are developed for selective CO methanation reactions. • A higher TiO 2 content of the TiO 2 /Al 2 O 3 composite increases Ru metal dispersion. • The high metal dispersion and low electron density of Ru promote CO methanation. • The highest activity at a TOF of 8.60 × 10−3 s−1 is exhibited by Ru3/Ti3/Al 2 O 3. • Introducing excess TiO 2 creates oxygen vacancies, facilitating CO 2 methanation. Hydrogen-rich gas derived from hydrocarbons contains large amounts of CO 2 and CO, with the latter being poisonous for low-temperature polymer exchange membrane fuel cell anodes. Therefore, the efficient removal of CO from reformate gases is crucial while minimizing the methanation of CO 2 to reduce unnecessary hydrogen consumption. In this study, Ru-based catalysts, which are ready to be employed in a chemical reactor, are developed to selectively convert CO into CH 4 with minimal CO 2 methanation using a simulated gas mixture composed of 75 % H 2 , 24 % CO 2 , and 1 % CO. The CO adsorption capability of Ru catalysts was enhanced by controlling the surface pores with a TiO 2 coating layer. In this process, egg-shell type TiO 2 /Al 2 O 3 supports were synthesized by wet impregnation method, and then Ru was impregnated on the supports. This modification enabled the Ru/TiO 2 /Al 2 O 3 to preferentially adsorb CO over CO 2. Furthermore, by systematically varying the TiO 2 loading, the electronic structure of Ru is modified to induce CO adsorption, resulting in a catalyst with maximum activity for selective CO methanation. The catalyst demonstrates a turnover frequency value of 8.6 × 10−3 s−1 at 190°C, surpassing the performance of previously reported catalysts. [ABSTRACT FROM AUTHOR]

ReaxFF molecular dynamics is employed to investigate interactions between water, ethanol, their mixture, and hydrated TiO 2 (101) surfaces. Water maintains hydration, while exchanging both hydrogen and oxygen atoms with the surface. Ethanol dissociates, leading to the formation of ethoxy radicals (CH 3 CH 2 O) permanently attached to the surface, water molecules, and acetic acid (CH 3 CO 2) species. Ethoxy reduces the number of hydroxyl groups and hinders hydrogen migration across the surface. The mixture of water, ethanol, and TiO 2 (101) results in a reduction of ethoxy coverage, inhibits CH 3 CO 2 formation, and increases hydroxyl coverage, indicating the dominant role of water. Potential of mean force analysis shows that hydroxyl formation follows exothermic paths, with activation energy lower than 0.45 eV. A narrower pathway for ethanol access to its adsorbed site is a key factor in the dominance of water. The formation of H 2 molecules exhibits a prohibitive energy barrier (> 4 eV), suggesting that catalytic pathways, rather than purely surface reactions, could be favored. • Exploring liquid ethanol/water interaction with hydrated-TiO 2 (101). • Ethanol dissociation lowers TiO 2 hydration and hydrogen mobility. • Water dominates the surface interactions when mixed with ethanol. • Unravel mechanisms and energetics of surface hydration via water or ethanol molecules. • Calculation of the formation of H 2 , showing the prevalence of catalytic mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Different contents of Pt were incorporated into TiO 2 structures and annealed at various temperatures. • Pt at 0.096 wt% boosted the photocatalytic efficiency of TiO 2 for acetaldehyde oxidation. • The 130 °C annealed sample showed the highest activity at various humidity values (0, 30, 60 % RH). • Unique single-Pt-atom structure coordinated with ammonia or ammonium species on a TiO 2 lattice. • Unique photocatalytic structures affect the activity by controlling Pt content and annealing temperatures. The effects of incorporation of various amounts of Pt into TiO 2 photocatalysts on the removal of acetaldehyde under visible light and 60% RH were investigated. Pt at 0.096 wt% boosted the photocatalytic efficiency of TiO 2 , while further increased Pt amount resulted in a decrease in activity. The enhanced activity can be ascribed to small amounts of Pt and dispersed individual Pt atoms on TiO 2. Furthermore, among the 0.096 wt% Pt-TiO 2 samples with diverse annealing temperatures (100, 130, 200, 375, and 525 °C), the 130 °C annealed sample exhibited the highest activity at various humidity values (0, 30, and 60% RH). This superior performance can be attributed to its unique single-Pt-atom structure coordinated with ammonia or ammonium species on a TiO 2 lattice, as evidenced by TOF-SIMS results. Our findings show how unique photocatalytic structures alter catalytic activity by controlling Pt content and annealing temperatures, which will be critical for real-world applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly controlled synthesis method for developing ZnO/TiO 2 Core/shell nanoarrays. • Enhanced sensing performance of core/shell compared to pristine ZnO nanoarrays. • UV and external bias reduce the working temperature from 350° to 45 °C. • The sensors showed significant sensing performance under light and external bias. Well-aligned ZnO-TiO 2 core–shell nano-arrays (NAs) were synthesized by uniformly coating a thin layer of TiO 2 (either ∼ 30 or ∼ 50 nm) on the ZnO NAs. The TiO 2 -coated ZnO NAs were annealed carefully to preserve the ZnO-TiO 2 core–shell NA structure and to limit the formation of any mixed metal oxides (i.e., zinc titanate: Zn x TiO y). The ZnO-TiO 2 core–shell NAs acetone gas sensing response was investigated by measuring the current when applying bias voltages ranging between 0.1 and 9 V DC, with and without ultraviolet (UV) illumination. The sensitivity, selectivity, and repeatability at operating temperatures ranging from 45 to 350 °C are analyzed and discussed in detail. The ZnO-TiO 2 core–shell NAs sensors under UV light illumination significantly improved sensing performance compared to dark conditions. At 45 °C, the 50 nm TiO 2 -coated ZnO NAs sensor showed a limit of detection (LoD) of 16 ppb under UV illumination, highlighting its utility in applications requiring fast, accurate detection of acetone vapor. [ABSTRACT FROM AUTHOR]

TiO 2 aerogels with high surface oxygen vacancies were fabricated by sol–gel method followed by supercritical drying. Density functional theory revealed that abundant surface oxygen vacancies endow TiO 2 aerogels with high electrostatic potential, which promotes the formation of stable surface charge transfer complexes and allows significant charge transfer from molecules to TiO 2 aerogels. [Display omitted] • TiO 2 aerogels with high surface oxygen vacancies were fabricated. • TiO 2 aerogels showed narrower band gap and higher electron density of states. • TiO 2 aerogels exhibited excellent SERS performance. • Density functional theory further revealed the SERS mechanism. The exploration of new and high-performance semiconductor substrates has always been one of the most important research directions in SERS technology. However, the low sensitivity of semiconductor SERS substrates limits their application. Herein, TiO 2 aerogels with high surface oxygen vacancies were fabricated by sol–gel method followed by supercritical drying. Compared with traditional semiconductor materials, TiO 2 aerogels exhibit low detection limits (1 × 10–7 M) for 4-mercaptobenzoic acid molecules. Moreover, density functional theory further revealed that abundant surface oxygen vacancies endow TiO 2 aerogels with high electrostatic potential, which promotes the formation of stable surface charge transfer complexes and allows significant charge transfer from molecules to TiO 2 aerogels. It is worth noting that the narrower band gap and higher electron density of states of TiO 2 aerogels effectively enhance the vibrational coupling in the substrate-molecule system, leading to significant SERS activity of TiO 2 aerogels. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-step solid state calcination and reduction method was proposed. • Black Ag/TiO 2-x was synthesized with close interface and enhanced charges transfer. • Ag/TiO 2-x holds full spectrum respond and enhanced light absorption. • Ag/TiO 2-x exhibits robust photothermal synergistic VOCs degradation performance. Titanium dioxide (TiO 2) is a widely used low-cost and stable photocatalyst, but its wide bandgap and low quantum efficiency usually lead to poor photocatalytic performance. Herein, one-step solid state calcination and reduction method was proposed for simultaneously introducing surface defects and loading Ag nanoparticles (NP) on TiO 2. The as-obtained black TiO 2-x supported Ag NP (or Ag/TiO 2-x) holds a narrow bandgap to respond to the full solar spectrum due to the presence of high concentration surface vacancies, enhanced light absorption through the surface plasmon resonance effect of Ag NP, and satisfactory photothermal effects. Moreover, such a one-step solid state synthesis method leads to closely linked interface and enhanced charges transfer between Ag NP and TiO 2-x. Accordingly, Ag/TiO 2-x exhibits robust photothermal synergistic VOCs degradation performance with a toluene degradation rate 6 times higher than the reference Ag/TiO 2 (DP) prepared by the conventional solution method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous TiO 2 (SMTiO 2) was S-functionalized to adsorbed Au 9 nanoclusters (NCs) onto its surface. • XPS and HAADF-STEM were used to determine the size and agglomeration status of the adsorbed Au 9 NCs. • SMTiO 2 can adsorbed more NCs with lesser agglomeration than unmodified mesoporous TiO 2. • The Au 9 /SMTiO 2 degrades under UV light methyl orange (MO) twice as fast than SMTiO 2. • Response surface methodology using Python was applied to study MO degradation. Au 9 nanoclusters (Au 9 NCs) were deposited onto S-functionalized mesoporous TiO 2 (SMTiO 2) to produce efficient photocatalysts for Methyl Orange (MO) dye degradation with UV light. The morphology, the surface composition and the size of the deposited Au 9 NCs of the catalyst was analysed. SMTiO 2 could adsorb more clusters with lesser Au 9 cluster agglomeration than unmodified MTiO 2. This finding is attributed to the capability of the thiol groups to form strong bonds with the Au 9 clusters. To study Au 9 NCs effect on dye degradation activity, the MO degradation reaction constants under UV-light irradiation for SMTiO 2 nanoparticles (NPs) and Au 9 NCs decorated SMTiO 2 photocatalysts were studied, which were 0.07 min−1 and 0.149 min−1, respectively. Hence, it takes almost half the time to completely degrade MO using Au 9 NCs decorated SMTiO 2 photocatalysts compared to SMTiO 2 substrate. Results were analysed using the response surface methodology (RSM) to study the interaction between the reaction parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • A modified and advanced photoelectrocatalytic method was originally proposed. • This method involves 1D/2D TiO 2 /graphene anode and functionalized-graphene cathode. • This method exhibited a removal rate of 90.5% and super-fast kinetic rate. • The mechanism includes enhanced electrosorption, coordination and reduction. Electro/photo/photoelectro-catalytic technologies have shown huge potential for U(VI) capture. However, current researches mainly focus on designing various electrode materials, but rarely on the significance of structure match and cooperative working mechanism of anode and cathode for U(VI) removal. Here, a multi-mechanism co-driven (MMCD) photoelectrochemical method, involving electrosorption, micro electric-field attraction, coordination and photoelectrocatalytic reduction, was originally proposed. Through purposeful design of an advanced asymmetrical photoelectrocatalytic system, consisting of 1D/2D TiO 2 /graphene (GTR) photoanode and xanthan gum-polyacrylic acid bound graphene (RGX) cathode, the MMCD system exhibited enhanced photoelectrocatalytic activity, fast electron transfer ability, and abundant binding active groups, which drove U(VI) ions to fast electro-migrate towards the surface of RGX cathode, then form micro electric-field attraction and coordination with electronegative O-containing groups, and finally be catalytically reduced into electroneutral sediments with the aid of photoelectrons from GTR anode. Ultimately, the MMCD system displayed a high removal rate of 90.5 % at 1.0 V, 1.7 times and 4.5 times that of electrochemical and photocatalytic methods. Its kinetic rate was also 71 % and 296 % faster than that of the latter two methods. Meanwhile, this system also exhibited an improved reduction efficiency of U(VI) to U(IV), high selectivity as well as good reusability. [ABSTRACT FROM AUTHOR]