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TiO2-based catalysts with various surface heterostructures (0D, 1D, 2D, and 3D) have been widely researched owing to their cost-effectiveness, high stability, and environmentally friendly nature, and can be used for many applications in various fields, including hydrogen production and pollutant degradation. However, there are also many existing problems limiting their practical application, such as their large band gap and rapid electron–hole recombination rate. Owing to the abundance of recent achievements in materials science, we will summarize the recent structural engineering strategies which provide favorable photocatalytic activity enhancements, such as enhanced visible light absorption, stability, an increased charge–carrier separation rate and improved specific surface area. Among the various structural engineering methods in this review, we will introduce TiO2-based materials with different dimensional structures. Meanwhile, we also discuss recent achievements in synthesis methods and application of TiO2-based catalysts in various fields. We aim to display a comprehensive overview which can be a guide for the development of a new generation of TiO2-based catalysts according to their structural design for enhanced solar energy conversion. [ABSTRACT FROM AUTHOR]

Multifunctional road marking coatings with the functions of high-temperature stability, degradation of exhaust gas, and self-cleaning are of great significance for the safe operation and environmental protection of tunnels. This article uses active acrylic resin and an organosilicon hydrophobic agent as the base material, selects expanded vermiculite and glass microspheres as insulation fillers, and uses ammonium polyphosphate, pentaerythritol, melamine, and aluminum hydroxide as high-thermal-stability systems to prepare a two-component road marking coating base material. Then, nano SiO2 and modified nano TiO2 are added as modifiers to prepare a multifunctional road marking coating for tunnels. The physical and chemical properties of multifunctional road marking coatings are evaluating based on laboratory tests including thermogravimetry and derivative thermogravimetry, differential scanning calorimetry, infrared spectroscopy, scanning electron microscopy, exhaust degradation, and contact angle tests. The results indicate that the developed multifunctional road marking coating effectively reduces the thermal conductivity of the carbon layer through physical changes in the flame retardant system and the heat resistance formed by the high breaking bond energy of nano SiO2 during the combustion process. It forms a ceramic-like structure of titanium pyrophosphate with nano TiO2 that is beneficial for improving flame retardancy without generating harmful volatile gases and has good flame retardant properties. N–V co-doping reduces the bandgap of TiO2, broadens the absorption range of visible light by nano TiO2, improves the catalytic efficiency of visible light, and achieves the degradation efficiency of the four harmful components NOx, HC, CO, and CO2 in automotive exhaust by 23.4%, 8.3%, 2.5%, and 2.9%, respectively. The solid–liquid phase separation in the multifunctional road marking coating in the tunnel causes the formation and accumulation of nano SiO2 and TiO2 particles on the coating surface, resulting in a microstructure similar to the "micro–nano micro-convex" on the lotus leaf surface and making a water droplet contact angle of 134.2° on the coating surface. [ABSTRACT FROM AUTHOR]

Cerium element with a unique electric structure can be used to modify semiconductor photocatalysts to enhance their photocatalytic performances. In this work, Ce-doped TiO2 (Ce/TiO2) was successfully achieved using the sol-gel method. The structural characterization methods confirm that Ce was doped in the lattice of anatase TiO2, which led to a smaller grain size. The performance test results show that the Ce doped in anatase TiO2 significantly enhances the charge transport efficiency and broadens the light absorption range, resulting in higher photocatalytic performance. The Ce/TiO2 exhibited a photocurrent density of 10.9 μA/cm2 at 1.0 V vs. Ag/AgCl, 2.5 times higher than that of pure TiO2 (4.3 μA/cm2) under AM 1.5 G light. The hydrogen (H2) production rate of the Ce/TiO2 was approximately 0.33 μmol/h/g, which is more than twice as much as that of the pure anatase TiO2 (0.12 μmol/h/g). This work demonstrates the effect of Ce doping in the lattice of TiO2 for enhanced photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Hydrogen, as a clean and pollution-free energy with high calorific value, is one of the best alternatives to fossil fuels. Hydrogen evolution reaction (HER), as a half reaction of electrochemical water splitting, has also received extensive attention. At present, the development of low-cost and high-performance hydrogen evolution catalysts still faces enormous challenges. In this work, we synthesized a series of RuNi/TiO 2 -oxMWCNT catalysts with different Ru and Ni ratio. After optimizing the composition and proportion, RuNi/TiO 2 -oxMWCNT with Ru:Ni=4:6 has the optimal hydrogen evolution performance. High HER performance of extremely low 14.8 mV overpotential at 10 mA·cm−2 and 38.4 mV·dec−1 Tafel slope with perfect stability is achieved, which is superior to most reported ruthenium-based catalysts and even commercial Pt/C. XPS and UPS indicates that there is a metal synergistic effect of Ru and Ni and a strong SMSI between Ru and TiO 2 in the RuNi/TiO 2 -oxMWCNT catalyst, which helps to improve hydrogen evolution performance. This study provides a pathway for the rational design of multi-component nanostructured catalysts for HER. [Display omitted] • Bimetallic RuNi/TiO 2 -oxMWCNT catalysts were successfully fabricated by deposition-precipitation method. • The strong metal carrier interaction between Ru and TiO 2 optimizes the electronic structure of the catalyst. • The synergistic effect of bimetallic Ru-Ni tremendously improved the hydrogen evolution performance of catalysts. • The RuNi/TiO 2 -oxMWCNT shows an excellent HER performance with the low overpotential and Tafel slope. [ABSTRACT FROM AUTHOR]

Abstract In this study, a facile solution method is proposed for synthesizing popcorn-like TiO 2 aggregations (P-TiO 2) as the light scatterers in the photoanode of DSSCs. This novel solution method is promising due to the less time and lower temperature required for carrying out the reaction, comparing to those for the conventional hydrothermal synthesis. The P-TiO 2 has the size of 300 nm and is composed of small nanoparticles with the size of 50 nm. Also, different from the common light scatterers, the P-TiO 2 has a special anatase phase which is beneficial for dye adsorption and charge transfer. The highest solar-to-electricity conversion efficiency of 7.56% is obtained for the DSSC with the photoanode composed of the commercial P90 TiO 2 dye-adsorption layer and the P-TiO 2 light scattering layer, due to the large surface area, highly active anatase nature, and the excellent light scattering ability for the home-made P-TiO 2. The results suggest that the photovoltaic performance of DSSCs can be efficiently improved by carefully designing the morphology of the TiO 2 nanostructure in the photoanode with large surface area and unique configuration to confine the incident light in the electrode for longer time. Graphical abstract Image 1 Highlights • Novel synthesis of Popcorn-like TiO 2 light scatterers. • High conversion efficiency is by light scattering layer. • High performance is due to well-defined structure. [ABSTRACT FROM AUTHOR]

Ce/N co-doped TiO 2 /NiFe 2 O 4 /diatomite (CN-TND) hybrid catalyst was prepared via sol-gel method. This ternary composite combined the advantages of three components: adsorption capability of diatomite (Dt), visible-light-driven photoactivity of Ce/N co-doped TiO 2 (Ce/N-TiO 2 ), and magnetic recyclability of ferrite NiFe 2 O 4 . The physicochemical properties of CN-TND were characterized by various analytical methods. The visible-light-driven photoactivity of CN-TND was investigated by the degradation of tetracycline (TC) and disinfection of Escherichia coli ( E. coli ) under visible light irradiation, and the optimal amount of Ce dopant was determined. In addition, the kinetic data of the degradation process were obtained, and the mechanism of this process was proposed. Different scavengers detected the active species involved during the degradation process. CN-TND exhibited ferromagnetism, thus it could be simply separated from the reactor by an external magnet. The reusability test proved its excellent photocatalytic stability and recyclability. We consider it suitable for the application of wastewater treatment. [ABSTRACT FROM AUTHOR]

TNTAs were grown by anodization of titanium in mixed electrolytes consisting of water, ethylene-glycol and NH4F. With this electrolyte composition, the obtained nanotube layers show a high level of flexibility towards controllable tube geometries. We carefully investigated the internal relationship between the synthesis parameters and the resulting TNTA morphology, deriving a set of relations to link the preparation parameters with the geometric dimensions of the obtained TNTAs. We show that the nanotube outer diameter not only increases linearly with the applied anodization voltage, but also relates to the water content in the electrolyte, and that both the water content and fluoride content determines the kinetics of the tube growth. Thus, by adjusting the electrolyte composition and optimizing the anodization procedure, a wide range of pre-defined morphologies can be realized. [ABSTRACT FROM AUTHOR]

The photocatalytic film Ce doped V x O y /TiO 2 was loaded on cordierite honeycomb (CHC), and this composite was prepared by sol-gel and dipping method, with Ce, oxides of V and TiO 2 as dopant and key substances, respectively. Using gaseous 1,2-dichlorobenzene to replace dioxin as target pollutant, dual degradation experiments at 140–280 °C were carried out (thermal decomposition and photodegradation), and the effects of preparation conditions on catalytic activity were investigated: doping amount of Ce, dipping time in the gel, the concentration of ammonium metavanadate (NH 4 VO 3 ) solution, dipping time in NH 4 VO 3 solution, sintering temperature. The gaseous samples were taken before and after the reactor and analyzed by gas chromatography. According to the results, the optimal preparation conditions were determined, and the corresponding removal rate was above 95% after 90 min of degradation at 280 °C. The composite was examined by ultrasonic to analyze the adhesive strength between the film and CHC, and further characterized by XRD and SEM. Furthermore, flue gas from waste incinerator was chosen as target pollutant, which contained PCDD/Fs, the industrial sidestream degradation experiment was carried out and showed excellent removal efficiency of the composite, the removal rate of PCDD/Fs reached ca. 90% after 90 min of degradation. [ABSTRACT FROM AUTHOR]

• Triphenylamine-porphyrin dyads are synthesized for photocatalysis. • XZP2/TiO 2 exhibits the most efficient charge separation as photoelectrode. • XZP2/TiO 2 performs the best in photodegradation of acid black and tetracycline. • Photocatalytic mechanism and interfacial charge transfer pathways are proposed. [Display omitted] Three triphenylamine (TPA) substituted dichromophoric zinc porphyrins XZP1–3 and a single zinc porphyrin ZP1 have been rationally designed to construct dye-sensitized TiO 2 nanoparticles to explore the feasibility of dichromophoric dye design for photocatalysis. TPA, N,N -diphenyl-(1,1′-biphenyl)− 4-amine and a carbazole-diphenylaniline derivative are attached to the meso -position of porphyrin core as the second chromophore. The electronic structure of the porphyrins is studied by density functional theory (DFT) calculations and the dye-sensitized composites are investigated using couples of spectral and electrochemical techniques. XZP2/TiO 2 exhibits the smallest charge transfer resistance and the longest electron lifetime among the investigated composites. The same catalyst performs the highest efficiency in photodegradation of both acid black (AB1) and tetracycline (TC) polluted water samples. Electronic paramagnetic resonance and radical quenching experiments reveal that the priority reactive species are superoxide radicals (•O 2 −) and holes (h+), suggesting the efficient charge separation at the porphyrin-sensitized TiO 2 interface. This work demonstrates the facilitated interfacial charge separation using dichromophoric dye-sensitized semiconductor particles for photodegradation and, the insights should aid in dyad design for photocatalysis application. [ABSTRACT FROM AUTHOR]

Abstract: The microstructure and electric properties of the rhombohedral–tetragonal morphotropic phase boundary (MPB) composition 0.8Bi1/2Na1/2TiO3–0.2Bi1/2K1/2TiO3 have been investigated. X-ray and electron diffraction results substantiate the co-existence of tetragonal and rhombohedral phases. The ferroelectric domains were clearly observed by electron microscopy. The oxygen octahedron tilting of the samples was studied by SAED. Both saturated polarization–electric field and butterfly shaped strain–electric field hysteresis loops prove that the MPB composition shows typical ferroelectric nature. The detailed microstructure–property characterization may shed light on the physical property of further work on BNT–BKT around morphotropic phase boundary. [Copyright &y& Elsevier]

The far-infrared ray (FIR) is one kind of electromagnetic wave employed for numerous bio-interactive applications such as body thermoregulation, infrared therapy, etc. Tuning the FIR-emitting property of the functional textile surface can initiate a new horizon to utilize this property in sportswear or even smart textiles. Ceramic particles were studied for their unique ability to constantly emit FIR rays. The purpose of this research is to characterize the FIR emission properties and the thermogravimetric analysis of ceramic-embedded polyurethane films. For this purpose, ceramic particles such as aluminum oxide, silicon dioxide, and titanium dioxide were incorporated (individually) with water-based polyurethane (WPU) binder by a sonication technique to make a thin layer of film. Significant improvement in FIR emissive property of the films was found when using different ceramic particles into the polyurethane films. Reflection and transmission at the FIR range were measured with a gold integrating sphere by Fourier-transform infrared (FTIR) spectrometer. The samples were also characterized by thermogravimetric analysis (TGA). Different physical tests, such as tensile strength and contact angle measurements, were performed to illustrate the mechanical properties of the films. The study suggested that the mechanical properties of the polyurethane films were significantly influenced by the addition of ceramic particles. [ABSTRACT FROM AUTHOR]

Niobium-doped titania (TNO) film can be used as a transparent conductive oxide (TCO) film due to its excellent conductivity and visible transparency. The performances of TNO sputtering targets are thus critical issues in optimizing sputtered films. This study clarifies the influences of inert and reducing atmospheres on the microstructure, densification, crystal structure, and electrical properties of TNO sputtering targets. The results indicate that a sintering atmosphere of 90% Ar–10% H 2 can result in a lower sintered density, larger grain size, and lower resistivity than can an atmosphere of Ar, followed by one of air. Sintering in 90% Ar–10% H 2 or Ar obviously decreases the resistivity of TiO 2 , from >10 8 Ω cm to <10 −1 Ω cm, and the TNO target, from >10 1 Ω cm to <10 −1 Ω cm. The resistivity of TNO target sintered at 1200 °C in 90% Ar–10% H 2 is as low as 1.8×10 −2 Ω cm. [ABSTRACT FROM AUTHOR]

Design of catalyst particles bearing excellent diffusion performance and suitable surface wettability is of great importance to the successful application of Pickering interfacial catalysis. In this study, selective oxidation reactions over hydrophobized hollow TS-1 zeolite were applied as probe reactions to investigate the influence of catalyst diffusion performance closely related to mesopore size on its catalytic activity. Hydrophobized hollow TS-1 zeolite particles were prepared via a post desilication treatment accompanied with precrystallization treatment. The synthesized hydrophobized hollow TS-1 zeolite was characterized by Scanning electron microscopy, Transmission electron microscopy, X-ray diffraction, UV–vis absorption spectrometry, Fourier-transform infrared spectroscopy and Nitrogen adsorption-desorption. Stable Pickering emulsions including 1-hexene-hydrogen peroxide, cyclohexene-hydrogen peroxide and cyclohexanone-water were prepared with hydrophobized hollow TS-1 zeolite particles as emulsifier. HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum values of 43.9 mol/(Ti-mol·h) for 1-hexene epoxidation, 15.7 mol/(Ti-mol·h) for cyclohexene epoxidation and 247.3 mol/(Ti-mol·h) for cyclohexanone ammoximation. In addition, HTS-1–393(2)-S zeolite particles displayed good reusability for more than five cycles. HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum TOF values for 1-hexene epoxidation, cyclohexene epoxidation and cyclohexanone ammoximation in Pickering interfacial catalysis system. [Display omitted] • Hydrophobized hollow TS-1 zeolite was prepared via a post desilication and a post silylation modification treatment. • HTS-1–393(2)-S zeolite synthesized with precrystallization at 393 K for 2 h presented the maximum TOF value. • Precrystallization handlement induces a reduction of emulsion droplet size for HTS-1–393(2)-S zeolite. • Precrystallization handlement leads to decreased tetra-coordinated titanium and increased anatase TiO 2. [ABSTRACT FROM AUTHOR]

Highly active Ni 2 P catalyst supported on core-shell structured Al 2 O 3 @TiO 2 for hydrodeoxygenation (HDO) of benzofuran (BF) was prepared and the effect of water on the performance for BF HDO over as-prepared catalyst was studied. The hydrophobic TiO 2 shell can enhance the catalytic activity, water resistance and HDO stability of the Ni 2 P/Al 2 O 3 catalyst. The Ni 2 P/A@T exhibited the highest HDO activity of 95% with O-free products yield of 87%, which is an increase of 40% when compared with that found for Ni 2 P/Al 2 O 3 (47%). [ABSTRACT FROM AUTHOR]

TiO 2 is one of the more promising anode materials for sodium-ion batteries, but its poor electrical conductivity and slow Na+ diffusion kinetics limit its further development. Herein, C, N, P self-doping KTi 2 (PO 4) 3 /TiO 2 composites were successfully prepared by using lotus pollen as bio-template. And the experimental results show that the introduction of heteroatom and KTi 2 (PO 4) 3 into TiO 2 greatly contributes to improving the conductivity and Na+ mobility of TiO 2. The strategies provided in this paper can not only provide new ideas for the design and preparation of anode materials for TiO 2 -based sodium-ion batteries, but also provide new directions for the utilization of natural biomass. [Display omitted] ● The C, N, P self-doped KTi 2 (PO 4) 3 /TiO 2 with yolk shell structure will improve the conductivity and Na+ mobility of TiO 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • The genotoxicity of TiO 2 NPs was confirmed at the single-cell level. • CINP, RPA3, and PRKACA served as biomarkers of TiO2 NPs exposure. • 5 nm and 14 nm TiO 2 NPs caused a response similar to antivirus defense. • Unique gene expression patterns were found within the same exposure of TiO2 NPs. Titanium dioxide nanoparticles (TiO 2 NPs) have attracted substantial attention in various applications, including environmental remediation and nanomedicine. A detailed understanding of the toxicity of TiO 2 NPs and the underlying mechanisms is fundamental to further development of their environmental and biomedical applications. Herein, we determined the changes in the transcriptional profile of human bone marrow stromal cells (BMSCs) after a set of different sized TiO 2 NPs exposure using single-cell RNA-seq (scRNA-seq). By taking advantage of sensitivity of scRNA-seq, we found that TiO 2 NPs exposure led to profound changes in gene expression and DNA damage signaling played a pivotal role in cellular responses to TiO 2 NPs exposure. Smaller TiO 2 NPs (5, 14 nm) led to a response similar to antivirus defense, and bigger TiO 2 NPs (54, 135, and 228 nm) induced proliferation and differentiation changes in transcriptional levels. Validation experiments on representative genes showed that some genes might be served as biomarkers of TiO 2 NPs exposure. Furthermore, in vitro and in vivo analyses showed remarkable over-production of reactive oxygen species (ROS) but did not affect osteogenic differentiation potential in BMSCs. The results unveiled landscape changes in transcriptomes in BMSCs induced by TiO 2 NPs, which provides new insights into toxicity assessments of nanomaterials. [ABSTRACT FROM AUTHOR]