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The best use of photogenerated electrons and holes is crucial to boosting photocatalytic activity. Herein, a bifunctional dual‐cocatalyst‐modified photocatalyst is constructed based on CdS/MoO2/MoS2 hollow spheres for hydrogen evolution coupled with selective pyruvic acid (PA) production from lactic acid (LA) oxidation. MoS2 and MoO2 are simultaneously obtained from the conversion of CdMoO4 in one step. In a photocatalytic process, the MoS2 and MoO2 function as the reduction and oxidation centers on which photogenerated electrons and holes accumulate and are used for hydrogen evolution reaction (HER) and PA synthesis, respectively. By monitoring the intermediates, a two‐step single‐electron route for PA production is proposed, initiated by the cleavage of the α‐C(sp3)−H bond in the LA. The conversion of LA and the selectivity of PA can reach ca. 29 % and 95 % after a five‐hour reaction, respectively. [ABSTRACT FROM AUTHOR]

Regulating molecular structure of donor‐acceptor (D‐A) polymer is a promising strategy to improve photoactivity. Herein, a porous nanorod‐like D‐A polymer is synthesized via a strategy of supramolecular chemistry combined with subsequent calcination treatment. This polymer consists of benzene rings (D) and triazine (A) that are linked by amido bond (−CONH−). −CONH− further partially cracks into cyano groups (−C≡N) (A) under calcination. The ratio of benzene to triazine could be tuned to adjust the −C≡N content by varying the calcination atmosphere. Such regulation of molecular structure could modulate the band structure of D‐A polymer and endow it with unique porous nanorod‐like morphology, leading to the achievement of two‐electron oxygen reduction and two‐electron water oxidation and the improvement of exciton splitting, O2 adsorption and activation. These merits synergistically ensure a highly efficient and stable photocatalytic H2O2 production in pure water. [ABSTRACT FROM AUTHOR]

Regulating molecular structure of donor‐acceptor (D‐A) polymer is a promising strategy to improve photoactivity. Herein, a porous nanorod‐like D‐A polymer is synthesized via a strategy of supramolecular chemistry combined with subsequent calcination treatment. This polymer consists of benzene rings (D) and triazine (A) that are linked by amido bond (−CONH−). −CONH− further partially cracks into cyano groups (−C≡N) (A) under calcination. The ratio of benzene to triazine could be tuned to adjust the −C≡N content by varying the calcination atmosphere. Such regulation of molecular structure could modulate the band structure of D‐A polymer and endow it with unique porous nanorod‐like morphology, leading to the achievement of two‐electron oxygen reduction and two‐electron water oxidation and the improvement of exciton splitting, O2 adsorption and activation. These merits synergistically ensure a highly efficient and stable photocatalytic H2O2 production in pure water. [ABSTRACT FROM AUTHOR]

Graphdiyne is an emerging material widely used in photocatalysis. Its excellent physicochemical properties, such as nonuniform electron distribution, uniform pore distribution, excellent electron mobility, and high chemical stability, make it promising for solar fuel production. Given the rapid development of graphdiyne-based photocatalysts and their application in solar fuel production, a timely review of this field is urgently needed. This paper summarises the structure, properties, synthesis and characterisation of graphdiyne, and the achievements of graphdiyne-based photocatalysts in solar fuel production, including H2 evolution, CO2 reduction and N2 fixation. The challenges and outlook of graphdiyne-based photocatalysts for efficient solar fuel production are presented. This paper is expected to provide new insights into graphdiyne-based photocatalysts for solar fuel production. [ABSTRACT FROM AUTHOR]

TiO 2 usually exhibits good photocatalytic activity and stability, but requires UV irradiation (smaller than 387 nm) for effective photocatalytic reactions, thus greatly limiting its application range. It is highly desirable to develop visible-light driven photocatalysts with high photocatalytic performance under sunlight or daylight lamp irradiation. Herein, Bi 4 O 5 I 2 hierarchical architectures with high visible-light photocatalytic activity were fabricated by a microwave-assisted solvothermal method. Oil bath synthesis and direct hydrolysis were also applied to prepare bismuth oxyiodides for comparison. The Bi 4 O 5 I 2 hierarchical architectures obtained by microwave treatment exhibited the highest photocatalytic activity toward phenol degradation under visible-light irradiation. This is attributed to its more surface active sites and strongest internal electric field, originating from the highest specific surface area and thinnest nanosheet morphology, respectively. The prepared Bi 4 O 5 I 2 hierarchical architectured photocatalysts may find potential application in catalysis, separation technology, solar cell, biomedical engineering, and nanotechnology. This work will provide some new insight into the design and fabrication of visible-light photocatalysts. [ABSTRACT FROM AUTHOR]

Catalytic decomposition of formaldehyde (HCHO) at room temperature is an important method for HCHO removal. Pt-based catalysts are the optimal catalyst for HCHO decomposition at room temperature. However, the stability of this catalyst remains unexplored. In this study, Pt-TiO 2 (Pt-P25) catalysts with and without adsorbed halogen ions (including F − , Cl − , Br − , and I − ) were prepared through impregnation and ion modification. Pt-TiO 2 samples with adsorbed halogen ions exhibited reduced catalytic activity for formaldehyde decomposition at room temperature compared with the Pt-TiO 2 sample; the catalytic activity followed the order of F-Pt-P25, Cl-Pt-P25, Br-Pt-P25, and I-Pt-P25. Characterization results (including XRD, TEM, HRTEM, BET, XPS, and metal dispersion) showed that the adsorbed halogen ions can poison Pt nanoparticles (NPs), thereby reducing the HCHO oxidation activity of Pt-TiO 2 . The poison mechanism is due to the strong adsorption of halogen ions on the surface of Pt NPs. The adsorbed ions form coordination bonds with surface Pt atoms by transferring surplus electrons into the unoccupied 5d orbit of the Pt atom, thereby inhibiting oxygen adsorption and activation of the Pt NP surface. Moreover, deactivation rate increases with increasing diameter of halogen ions. This study provides new insights into the fabrication of high-performance Pt-based catalysts for indoor air purification. [ABSTRACT FROM AUTHOR]

Room-temperature catalytic decomposition of formaldehyde (HCHO) is considered as one of the most main methods for the removal of indoor HCHO due to its facile reaction conditions. Herein, high-surface area mesoporous Pt/TiO 2 hollow chains were synthesized in high yield by using a simple microwave–hydrothermal route, followed by a combined NaOH-assisted NaBH 4 -reduction deposition of Pt nanoparticles on the as-obtained TiO 2 surface. The catalytic activity for HCHO decomposition was evaluated at room temperature. The prepared Pt/TiO 2 hollow chains with an optimal Pt loading of 0.5 wt.% exhibited high catalytic activity and recyclability. The apparent reaction rate constant of HCHO oxidation over this catalyst was approximately 1.42 × 10 −3 ppm −1 min −1 , exceeding that of the commercial Degussa P25 TiO 2 with equal Pt content ( k = 5.36 × 10 −4 ppm −1 min −1 ) by a factor of approximately 2.65. The high catalytic activity of the Pt/TiO 2 hollow chains could be mainly attributed to the hollow chain-like structure, high specific surface area, numerous mesopores, and high pore volume of TiO 2 support. Consequently, the catalysts exhibited high adsorption capacity for HCHO, fast diffusion and transport of gas molecules, and good contact between gases and active sites. These characteristics enhanced the catalytic activity. [ABSTRACT FROM AUTHOR]

The production of solar fuel through photocatalytic water splitting and CO2 reduction using photocatalysts has attracted considerable attention owing to the global energy shortage and growing environmental problems. During the past few years, many studies have demonstrated that graphene can markedly enhance the efficiency of photocatalysts for solar-fuel generation because of its unique 2D conjugated structure and electronic properties. Herein we summarize the recent advances in the application of graphene-based photocatalysts for solar-fuel production, including CO2 reduction to hydrocarbon fuel and water splitting to H2. A brief overview of the fundamental principles for splitting of water and reduction of CO2 is given. The different roles of graphene in these graphene-based photocatalysts for improving photocatalytic performance are discussed. Finally, the perspectives on the challenges and opportunities for future research in this promising area are also presented. [ABSTRACT FROM AUTHOR]

Aufgrund des zunehmenden Energiebedarfs und wachsender Umweltprobleme erfahren die Produktion von Solarbrennstoffen durch photokatalytische Wasserspaltung und die CO2-Reduktion mithilfe von Photokatalysatoren beträchtliches Interesse. In den letzten Jahren haben zahlreiche Studien gezeigt, dass die Effizienz der Photokatalysatoren für die Produktion von Solarbrennstoffen deutlich gesteigert werden kann, wenn man Graphen verwendet, das eine besondere konjugierte 2D-Struktur und spezielle elektronischen Eigenschaften besitzt. Dieser Aufsatz gibt einen Überblick über jüngste Fortschritte bei der Anwendung von Photokatalysatoren auf Graphenbasis für die Produktion von Solarbrennstoffen einschließlich der CO2-Reduktion zu Kohlenwasserstoffen und der H2-Erzeugung mittels Wasserspaltung. Die Grundlagen der Wasserspaltung und der CO2-Reduktion werden kurz dargestellt. Die für die Verbesserung der photokatalytischen Leistung relevanten Funktionen des Graphens werden diskutiert. Mit Blick auf bestehende Herausforderungen und Möglichkeiten auf diesem vielversprechenden Gebiet werden schließlich mögliche Perspektiven erörtert. [ABSTRACT FROM AUTHOR]

Chlorine evolution reaction (CER) in chlor-alkali industry is limited by oxygen evolution reaction (OER) due to their common active sites and close standard reaction potentials. Herein, a ternary RuSnTi electrode was synthesized and exhibits a superior CER activity in saturated NaCl solution. Theoretical studies reveal that Ru dopant improves the electrical conductivity of RuSnTi by contributing Ru orbitals to the energy band curves through/near the Fermi level. RuSnTi delivers a current density of 96.6 mA cm−2 at potential of 1.15 V (saturated calomel electrode, SCE), much higher than that of the dimensionally stable anode (DSA). Moreover, the inhibitory effect of Sn species on OER endows RuSnTi with a high Cl 2 selectivity of 95.7%. Besides, RuSnTi shows good stability during long-term stability test by stably operating 240 h at 100 mA cm−2 in saturated NaCl solution (pH = 7), highlighting the great potential in practical application. This work provides new insights into the development of high-performance Ru-based CER electrodes. [Display omitted] • Cl 2 selectivity of RuSnTi was predicted based on adsorption energy of Cl− and OH− ions. • RuSnTi delivers a high current density of 96.6 mA cm−2 at potential of 1.15 V (vs. SCE). • RuSnTi exhibits the highest Cl 2 selectivity of 95.7% in neutral saturated NaCl solution. • RuSnTi shows excellent stability in neutral and acidic saturated NaCl solution. [ABSTRACT FROM AUTHOR]

Sluggish charge kinetics and moderate adsorption–desorption ability of gas molecules are major limitations for photocatalytic NO x elimination of bulk g-C 3 N 4. A hierarchical porous g-C 3 N 4 photocatalyst modified with N vacancies and charge channels (KCNN) was prepared by thermal polymerisation in KCl medium followed by quenching to increase the photocatalytic efficiency. The optimized KCNN sample exhibits highly enhanced photocatalytic NO removal rate (70.5%), which is superior to those of bulk g-C 3 N 4 (38.1%), porous g-C 3 N 4 (54.5%) and K-doped g-C 3 N 4 (58.6%), respectively. X-ray photoelectron spectroscopy and electron paramagnetic resonance data reveal the successful formation of N vacancy in g-C 3 N 4 framework. The enhanced activity of KCNN is ascribed to the enlarged surface area, expanded light absorption, low charge recombination efficiency and strong oxidation capability, respectively. In situ DRIFTS and density functional theory results suggest that the introduction of N vacancies and K+ ions enable control over NO adsorption and activation, leading to the implementation of a preferred pathway (NO → NO+ → NO 3 ‾) and reduction in the emission of toxic intermediates. This work presents a potential idea for improving the charge transfer of layered materials and optimising the diffusion/adsorption/activation of gas molecules for photocatalytic NO oxidation. [Display omitted] • A hierarchical porous g-C 3 N 4 with N vacancies and charge channels is successfully synthesized. • The optimized KCNN sample exhibits improved photocatalytic NO removal rate and toxic by-product suppression. • DFT calculations reveal that the N vacancies accelerate the adsorption and activation of NO on the g-C 3 N 4 surface. • In-situ DRIFTS revealed the photo-oxidation mechanism of NO on KCNN through a preferred pathway (NO → NO+ → NO 3 ‾). • The synergy of hierarchical porous structure, N vacancy and K+ ions boost photocatalytic NO x removal activity of KCNN. [ABSTRACT FROM AUTHOR]

The development of highly active single‐atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal‐support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1−CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt−O−Cu moieties, which modulates the d‐band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu−O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions. [ABSTRACT FROM AUTHOR]

The development of highly active single‐atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal‐support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1−CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt−O−Cu moieties, which modulates the d‐band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu−O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions. [ABSTRACT FROM AUTHOR]

High-efficiency DSSCs (dye-sensitized solar cells) based on multi-layered composite film photoanodes consisting of the TiO 2 blocking layer, the commercial Degussa P25 nanoparticles layer and 1D (one-dimensional) TiO 2 nanorods layer were fabricated. The 1D TiO 2 nanorods were prepared by a simple electrospinning technology and grinding process. The photovoltaic properties of different DSSCs based on nanoparticles/nanoparticles (DNP), nanorods/nanorods (DNR) and nanoparticles/nanorods (NPR) photoanodes were investigated and their photoelectric conversion efficiencies were 6.37, 4.92 and 8.03%. The dye-sensitized solar cells based on NPR photoanodes exhibited the best photovoltaic performance with a short-circuit current of 15.7 mA cm −2 . The enhanced photo-electricity performance of NPR solar cells could be attributed to the synergistic effect of following factors. (1) The P25 underlayer ensured intimate contact in DSSCs films structure and superior dye adsorption. (2) The nanorods overlayer with 1D structure showed strong light scattering ability, which significantly enhanced light harvesting efficiency. In addition, the 1D geometry of TiO 2 nanorods provided a fast and long charge carrier transfer pathway, thus improving the transfer of photo-induced electrons in the DSSCs. [ABSTRACT FROM AUTHOR]

Derived from a hollow TiO 2 nanoparticle (HNP) as underlayer and a TiO 2 spindle (SP) as light scattering overlayer, a new bilayer single-crystalline photoanode (HNP/SP) is fabricated for dye-sensitized solar cell (DSSC) application. The prepared bilayer TiO 2 photoanode and two comparative HNP/HNP and SP/SP ones are fully characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV–vis absorption spectroscopy and N 2 adsorption–desorption isotherms. An overall photoelectric conversion efficiency of 8.65% has been achieved for HNP/SP DSSC, which is 25% higher than that of HNP/HNP DSSC, and also far superior to that of SP/SP or conventional P25 DSSC. The improved photovoltaic performance of HNP/SP DSSC is attributed to the synergic effects, i.e. the single-crystalline bilayer structure favoring for rapid interfacial electron transport, the relatively large specific surface area of HNP for effective dye adsorption, and the 1D geometry of single-crystalline TiO 2 spindles for direct electron transport pathway and strong light scattering effect. [ABSTRACT FROM AUTHOR]

Tripropylamine (TPA) is a highly toxic and carcinogenic compound, therefore, TPA concentration in water must be monitored to protect health and the environment. In this paper, an electrochemiluminescent (ECL) sensor was fabricated by immobilising Ru(bpy)32+-modified CuO nanoparticles (NPs) on a TiO2 nanotube array (TN) electrode. Compared to an ECL sensor fabricated by immobilising Ru(bpy)32+ on a TN only electrode, the as-prepared sensor displays a 30 % enhanced ECL signal and a detection limit of 9.6×10−10 M at a signal-to-noise ratio=3 with the concentration of TPA in a range 1×10−9 to 1×10−5 M. The results from this study indicated a new approach for the enhancement of performance of ECL sensor in detecting TPA in water. [ABSTRACT FROM AUTHOR]

Highlights: [•] Oxidative decomposition of formaldehyde on Pt/TiO2 occurs at room temperature. [•] Fluoride poisoning phenomenon of Pt/TiO2 nanosheets is explained. [•] This poisoning is due to F-blocking of Pt catalytic active sites. [•] Pt/TiO2 nanosheet-type catalysts can be easily regenerated by washing with NaOH solution. [Copyright &y& Elsevier]

[Display omitted] • Hierarchical Pt/Co 3 O 4 -NiO catalyst prepared from MOFs with excellent activity. • Hollow and porous structure with low air resistance and fast diffusion channels. • Abundant active oxygen species at the interface between Co 3 O 4 and NiO. • Enhanced O 2 adsorption and activation due to the electron transfer from NiO to Pt. • Possible mechanism for HCHO oxidation over Pt/Co 3 O 4 -NiO proposed. Room-temperature catalytic decomposition is considered a predominant approach for the continuous and efficient elimination of indoor formaldehyde (HCHO). Herein, Co 3 O 4 -NiO hollow dodecahedra were prepared by using ZIF-67 as a precursor and decorated with 0.3 wt% platinum nanoparticles (Pt NPs). The hierarchical porous Pt/Co 3 O 4 -NiO catalyst exhibited an excellent room-temperature HCHO decomposition performance, and 93% conversion was achieved within 60 min. Numerous active oxygens at the interface between Co 3 O 4 and NiO and the oxygen vacancies generated during Pt deposition were favorable for the adsorption and conversion of HCHO to Dioxymethylene (DOM). Moreover, the electron transfer from NiO to Pt rendered Pt NPs more effective in adsorbing and activating O 2 molecules, thereby promoting the further oxidation of DOM to formate and CO 2. Importantly, the hierarchical structure of the Co 3 O 4 -NiO support with a large surface area participated in the uniform distribution and easy accessibility of Pt active sites. In addition, the hollow and porous structure enabled Pt/Co 3 O 4 -NiO catalyst to possess ultra-low gas resistance, which is important for gas–solid HCHO oxidation. This work may provide clues for the fabrication of MOF-derived catalysts for HCHO decomposition with high efficiency. [ABSTRACT FROM AUTHOR]

2D carbides and nitrides of transition metals, also known as MXenes, are an emerging class of 2D nanomaterials that have shown excellent performances and broad application prospects in the fields of energy storage, catalysis, sensing, electromagnetic shielding, electronics and photonics, and life sciences. This unusual diversity of applications is due to their superior hydrophilicity and conductivity, high carrier concentration, ultra-high volumetric capacitance, rich surface chemistry, and large specific surface area. However, it is difficult to make MXenes with the desired surface functional groups that deliver high reactivity and high stability, because most MXenes are extracted from ceramics (MAX phase) by an etching process, where a large number of metal atoms are inevitably exposed on the surface, with other anions and cations embedded uncontrollably. The exposed metal atoms and implanted ions are thermodynamically unstable and readily react with trace oxygen or oxygen-containing groups to form the corresponding metal oxides or degrade chemically, resulting in a sharp decline in activity and loss of excellent physicochemical properties. The addition of certain synergistic additives during the intercalation and chemical modification of surface functional groups under non-hazardous conditions can result in stable and efficient MXene-based materials with exceptional optical, electrical, and magnetic properties. This review discusses several such methods, mainly additive-mediated intercalation and chemical modification of the surface functional groups of MXene-based materials, followed by their potential applications. Finally, perspectives are given to discuss the future challenges and promising opportunities of this exciting field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyhedron MNC HS was synthesized using ZIF-67 as template. • It has a porous structure and large specific surface area. • It showed excellent adsorption capacity and good recovery for Congo red. • It can be as a promising candidate for removal of CR pollutants. Adsorption materials with large specific surface area and porous structures exert a beneficial impact on improving the adsorption performance. In this work, MgNiCo LDH hollow structure (MNC HS) is fabricated through a simple one-step solvothermal method using ZIF-67 as the sacrificial template. Electron microscopy shows that the MNC HS retains the dodecahedral shape of ZIF-67. The as-prepared sample exhibits efficient adsorption for Congo red (CR) in water, which is due to the hierarchical structure and large specific surface area that provides more adsorption sites and electrostatic interaction. The CR adsorption process fits the pseudo-second-order model better by kinetics simulation; while Langmuir model is more accurate than Freundlich model in describing the adsorption isotherms of CR. The maximum adsorption capacity calculated by the Langmuir model can reach 1194.7 mg g−1, which is much higher than that of the sample MgNiCo LDH (MNC) synthesized by conventional methods. The cycle tests also show that the as-prepared adsorbent has good stability and recycling ability. [ABSTRACT FROM AUTHOR]

Room‐temperature oxidation over supported noble metals provides a feasible approach to eliminating formaldehyde (HCHO) from indoor air. Oxygen activation by noble metals such as gold and platinum plays a key role in achieving complete HCHO oxidation, but it is unclear how different noble metals function synergistically toward oxygen activation. Here, the synergistic mechanisms of Pt and Au nanoparticles (NPs) coloaded on TiO2 in catalytic HCHO oxidation are elucidated. Strikingly, ≈0.08% doping of Pt can dramatically improve the catalytic activity of 0.9% Au/TiO2. The surface oxygen species of TiO2 jointly activated by Au and Pt NPs can rapidly transform HCHO to dioxymethylene surface species, while negatively charged Pt NPs can efficiently adsorb and activate molecular oxygen to oxidize the dioxymethylene into formate, which is further completely oxidized. This synergy enables efficient HCHO oxidation at surface sites between adjacent Pt and Au NPs. [ABSTRACT FROM AUTHOR]

Sodium hybrid supercapacitors (Na‐HSCs) are regarded as one promising electrochemical energy storage device, because of the low price of sodium, prolonged life cycle, and high‐energy/power density. Nonetheless, the imparity between the fast capacitive reactions at cathode and the sluggish Faradaic reactions at the anode leads to an imbalance in the electrochemical reaction kinetics, limiting the development of Na‐HSCs. Therefore, it is urgent to develop suitable anode materials for performance‐enhanced Na‐HSCs. Herein, sandwich‐shell‐structured CoMn2O4/C hollow spheres are synthesized by a facile hydrothermal reaction and subsequent calcination, where mesoporous carbon hollow spheres (CHSs) serve as nonsacrificial hard templates. CHSs with numerous mesoporous channels are beneficial for the penetration of reactant ions. Therefore, CoMn2O4 nanosheets are successfully deposited on the inner and outer surfaces of CHSs, generating sandwich‐shell‐structured CoMn2O4/C hollow spheres. Benefiting from the unique design, CoMn2O4/C HSs exhibit excellent sodium storage performance, including a high‐specific capacity of 290 mAh g–1 at 0.1 A g–1 and prolonged cycling durability. A Na‐HSC assembled by CoMn2O4/C HSs anode and activated carbon cathode exhibits a high‐energy density (265 Wh kg–1) and a wide‐operating voltage range (0.01–4.0 V). [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries, as viable options for energy storage, have gained popularity because of their high energy density. However, the poor conductivity of sulfur and Li2S, as well as the shuttling effect of lithium polysulfides, seriously limits their commercialization. Herein, cobalt chalcogenides (Co3O4, CoS, and Co3Se4) supported by reduced graphene oxide are synthesized as the electrode materials, which feature high conductivity, rapid kinetic conversion, and catalytic effect. Based on complementary experimental outputs and advanced computation, it is revealed that the change in anion results in distinctive performance. Among them, the cathode material based on Co3Se4/reduced graphene oxide is the best. The reasons can be ascribed to the conductive and catalytic improvement. This comparative study provides guidelines in the design of lithium‐sulfur batteries via the meticulous regulation of the anions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of bifunctional mesostructured alumina via amino-functionalization. [•] P123 extraction and tetraethylenepentamine loading were simultaneously realized. [•] The amino-functionalized alumina shows excellent mesostructure centering at 7.3nm. [•] Good adsorptive capability of the amino-functionalized alumina for Cr(VI) and CO2. [•] The amino-functionalized alumina shows very fast adsorption kinetics for Cr(VI). [ABSTRACT FROM AUTHOR]

In response to the increasing concerns over energy and environmental sustainability, photocatalytic water-splitting technology has attracted broad attention for its application in directly converting solar energy to valuable hydrogen (H2) energy. In this study, high-efficiency visible-light-driven photocatalytic H2 production without the assistance of precious-metal cocatalysts was achieved on graphene-Zn xCd1− xS composites with controlled compositions. The graphene-Zn xCd1− xS composites were for the first time fabricated by a one-step hydrothermal method with thiourea as an organic S source. It was found that thiourea facilitates heterogeneous nucleation of Zn xCd1− xS and in situ growth of Zn xCd1− xS nanoparticles on graphene nanosheets. Such a scenario results in abundant and intimate interfacial contact between graphene and Zn xCd1− xS nanoparticles, efficient transfer of the photogenerated charge carriers, and enhanced photocatalytic activity for H2 production. The highest H2-production rate of 1.06 mmol h−1 g−1 was achieved on a graphene-Zn0.5Cd0.5S composite photocatalyst with a graphene content of 0.5 wt %, and the apparent quantum efficiency was 19.8 % at 420 nm. In comparison, the graphene-Zn xCd1− xS composite photocatalyst prepared by using an inorganic S source such as Na2S exhibited much lower activity for photocatalytic H2 production. In this case, homogeneous nucleation of Zn xCd1− xS becomes predominant and results in insufficient and loose contact with the graphene backbone through weak van der Waals forces and a large particle size. This study highlights the significance of the choice of S source in the design and fabrication of advanced graphene-based sulfide photocatalytic materials with enhanced activity for photocatalytic H2 production. [ABSTRACT FROM AUTHOR]

The conversion of CO 2 into solar fuels via photo-driven catalytic reduction presents a promising avenue toward achieving carbon neutrality. Herein, copper-based catalysts are prepared and explored for photo-driven photothermal CO 2 reduction reaction. The optimized catalyst exhibits a consistent CO production rate of 165.9 mmol g−1 h−1 and 100% CO selectivity at ambient pressure. We unveil the intricate adsorption dynamics at play: H 2 molecules predominantly interact with and activate at Cu sites, while CO 2 molecules preferentially adsorb and activate at interfacial sites within the composites. Furthermore, we elucidate how the positive shift of the d-band center (ε d) for Cu 3 d orbitals significantly enhances H 2 adsorption and activation. Crucially, the subsequent dissociation of H 2 molecules at Cu sites drives the efficient conversion of adsorbed CO 2 molecules at interfacial sites into CO. Overall, our findings not only advance the theoretical understanding but also offer practical insights for realizing photothermal catalytic CO 2 reduction reactions. [Display omitted] • The optimized Cu/AO catalyst exhibits 100% CO selectivity at ambient pressure. • The variance in work function difference induces an upward shift of the d-band center. • The adsorption and activation of H 2 is facilitated by the upward shift of the d-band center of Cu nanoparticles. • Cu-AO interface plays a decisive role in the adsorption and activation of CO 2. [ABSTRACT FROM AUTHOR]

Room-temperature catalytic oxidation of formaldehyde (HCHO) has been extensively investigated due to its high efficiency, convenience, and environmental friendliness. Herein, nickel-iron layered double hydroxide (NiFe LDH) nanosheets were synthesized in-situ on a nickel foil (NF) using a facile one-step hydrothermal method, followed by the deposition of ultra-low content (0.069 wt%) of Pt nanoparticles through NaBH 4 reduction. The resulting three-dimensional (3D) hierarchical Pt/NiFe-NF catalyst exhibited exceptional activity for the complete decomposition of formaldehyde to carbon dioxide (CO 2) at room temperature (∼95 % conversion within 1 h), as well as remarkable cycling stability. The 3D porous structure of Pt/NiFe-NF provides fast transport channels for the diffusion of gas molecules, making the active catalyst surfaces more accessible. Moreover, abundant hydroxyl groups in NiFe LDH serve as adsorption centers for HCHO molecules to form dioxymethylene (DOM) and formate intermediates. Furthermore, electronic interactions between NiFe LDH and Pt enhance the adsorption and activation of O 2 on Pt surfaces, leading to the complete decomposition of intermediates into non-toxic products. This work presents new insights into the design and preparation of Pt-based 3D hierarchical catalysts with surface-rich hydroxyl groups for the efficient removal of indoor HCHO. [Display omitted] • 3D hierarchical porous structure reduces air resistance and accelerates gas diffusion. • Surface hydroxyl groups adsorb formaldehyde and convert it into intermediates. • Electronic interaction between Pt and NiFe LDH strengthens O 2 activation. • Excellent formaldehyde oxidation activity and recyclability with low Pt loading. [ABSTRACT FROM AUTHOR]

Organic‐inorganic halide perovskite solar cells (PSCs) have drawn tremendous attention owing to their remarkable photovoltaic performance and simple preparation process. However, conventional wet‐chemical synthesis methods inevitably create defects both in the bulk and at the interfaces of perovskites, leading to recombination of charge carriers and reduced stability. Herein, a bilateral interface modification to perovskites by doping room‐temperature synthesized CsPbBr3 nanocrystals (CN) is reported. The ultrafast transient absorption measurement reveals that CN effectively suppresses the defect at the SnO2/perovskite interface and boosts the interfacial electron transport. Meanwhile, the in situ Kelvin probe force microscopy and contact potential difference characterizations verify that the CN within the upper part of the perovskites enhances the built‐in electric field, facilitating oriented migration of the carriers within the perovskite. Combining the superiorities of CN modifiers on both sides, the bilaterally modified CH3NH3PbI3‐based planar PSCs exhibit optimal power conversion efficiency exceeding 20% and improved device stability. [ABSTRACT FROM AUTHOR]

Coupling photocatalytic H2 production with organic synthesis attracts immense interest in the energy and chemical engineering field for the low‐cost, clean, and sustainable generation of green energy and value‐added products. Nevertheless, the performance of current photocatalysts is greatly limited by grievous charge recombination and tardy H2 evolution. To tackle these issues, a Pt nanocluster‐modified ZnCdS solid solution is fabricated for photocatalytic H2 production and selective furfuralcohol oxidation. The internal electric field inside the ZnCdS and Schottky junction between ZnCdS and Pt nanoclusters drastically ameliorate charge separation. Meanwhile, the Pt nanoclusters remarkably expedite the H2 evolution kinetics on ZnCdS. As a result, the H2 production rate over Pt‐loaded ZnCdS reaches 1045 µmol g−1 h−1, which is about 26‐ and 70‐fold that of CdS and ZnS, respectively. Under light irradiation for 3 h, the conversion of furfuralcohol to furfural reaches 71% with 89% furfural selectivity. The photocatalytic mechanism is investigated by in situ characterizations and theoretical calculations. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hierarchical porous CdS nanosheet-assembled flowers were synthesized by a simple ion-exchange strategy using morphology-analogous Cd(OH)2 and Na2S as precursors. [•] The prepared CdS flowers exhibited high visible-light photocatalytic H2 production activity and 24.7% quantum efficiency at 420nm. [•] The ion-exchange strategy of Cd(OH)2 intermediates can be extended to the preparation of other porous oxides and sulfides with hierarchical nanostructures. [•] The hierarchical organization of nanosheets and porous nanosheet structures can efficiently enhance light-absorption ability and provide a greater number of active adsorption sites. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional hierarchical boehmite hollow microspheres with a very high yield at low cost were successfully synthesized via a one-pot template-free solvothermal route using aluminum chloride hexahydrate as precursor in a mixed ethanol–water solution with assistance of trisodium citrate. The as-synthesized products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption/desorption techniques. The results show that Cl− and addition amount of trisodium citrate have significant effect on the morphologies of the resultant products, and 6–8 mmol of trisodium citrate is optimal for the synthesis of boehmite hollow microspheres assembled from randomly interconnecting and aligned nanorods with solvothermal time no less than 15 h. A synergistic mediation mechanism of citrate ions and Cl− to form boehmite hollow spheres via self-assembly morphology evolution was proposed based on the experimental results. Interestingly, the typical boehmite hollow microspheres with a surface area of 102 m2 g−1, pore volume of 0.37 cm3 g−1, and the average pore size of 14.6 nm show superb adsorption properties for Congo red with maximum capacity of 114.7 mg g−1 which is higher than that of a commercial boehmite. This simple synthetic route is a very promising way for the design and synthesis of new functional hierarchical nanostructured materials with desired adsorptive properties. [Copyright &y& Elsevier]

Ag3PO4 spherical particles were synthesized by a facile precipitation method using silver nitrate and Na2HPO4 as precursors. The as-prepared samples had a high photocatalytic activity toward Rhodamine B (RhB) degradation under visible-light illumination. With increasing recycling times the photocatalytic activity first increased and then decreased. Based on systematic characterization of particles by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV/Vis absorption spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), a possible mechanism responsible for the improvement and subsequent decline of the photocatalytic performance of Ag3PO4 is proposed. Ag3PO4 spherical particles recycled for four times showed the highest photocatalytic activity because, according to our mechanism, Ag nanoparticles deposited on Ag3PO4 acted as electron trapping centers to prevent photogenerated electron-hole pairs from recombination. A further increase in the recycle times decreases the photocatalytic activity owing to the shielding effect by Ag layers on the surface of Ag3PO4. The results presented herein shed new light on the photostability of Ag3PO4 spherical particles and are potentially applicable to other photocatalytically active composites. [ABSTRACT FROM AUTHOR]

Abstract: The Ag/AgCl/TiO2 nanocomposite thin films are prepared on the pre-coated SiO2 soda-lime glass substrates by a sol–gel method for depositing TiO2 films, and then loaded with Ag/AgCl nanoparticles (NPs) by an impregnating precipitation photoreduction method. The as-prepared composite thin film exhibits a highly visible-light photocatalytic activity for degradation of 4-chlorophenol (4-CP) in water. The photocatalytic mechanism is proposed on the basis of the fact that the Ag NPs are photoexcited due to plasmon resonance, and then charge separation is accomplished by the transfer of photoexcited electrons from the Ag NPs to the TiO2 conduction band and the simultaneous formation of OHand Cl0, which cause the photocatalytic degradation of organic pollutants. The proposed mechanism is further confirmed by the detection of hydroxyl radicals. On the other hand, 4-CP can also be oxidized directly by plasmon-induced h+ (or Ag+) on Ag NPs, thereby accelerating the photooxidized Ag NPs back to their initial state. Therefore, the Ag NPs can be rapidly regenerated and the Ag/AgCl/TiO2 system remains self-stability. [Copyright &y& Elsevier]

Abstract: Hollow microspheres of hierarchical Zn–Al layered double hydroxides (LDHs) were synthesized by a simple hydrothermal method using urea as precipitating agent. The morphology and microstructure of the as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), nitrogen adsorption–desorption isotherms and fourier transform infrared (FTIR) spectroscopy. It was found that the morphology of hierarchical Zn–Al LDHs can be tuned from irregular platelets to hollow microspheres by simply varying concentrations of urea. The effects of initial phosphate concentration and contact time on phosphate adsorption using various Zn–Al LDHs and their calcined products (LDOs) were investigated from batch tests. Our results indicate that the equilibrium adsorption data were best fitted by Langmuir isothermal model, with the maximum adsorption capacity of 54.1–232mg/g; adsorption kinetics follows the pseudo-second-order kinetic equation and intra-particle diffusion model. In addition, Zn–Al LDOs are shown to be effective adsorbents for removing phosphate from aqueous solutions due to their hierarchical porous structures and high specific surface areas. [Copyright &y& Elsevier]

Abstract: A new flexible approach is developed to synthesize PbWO4 nanoparticles inside the channels of mesoporous silica SBA-15. Mesoporous SBA-15 silica with 7nm pores was produced by a hydrothermal process and used as a hard template. PbWO4 nanoparticles were synthesized and incorporated into the mesoporous silicate support in a low-power ultrasonication condition. The as-synthesized samples were characterized by Raman spectroscopy, diffuse reflectance UV–vis spectroscopy (UV–vis), powder X-ray diffraction (XRD), small-angle X-ray diffraction (SAXRD), nitrogen adsorption and transmission electron microscopy (TEM). It was found that PbWO4 nanoparticles appeared among the channels of SBA-15. Blue shift was observed in UV–vis absorption spectra due to the quantum size effect of PbWO4 nanoparticles. This preparation method is also capable of synthesis of various semiconductor nanoparticles with controlled size and morphology inside the channels of mesoporous materials. [Copyright &y& Elsevier]

Abstract: Exploring anatase TiO2 with superior thermal stability and photocatalytic activity is of great importance and challenging. In the present work, surface-fluorinated anatase TiO2 nanosheets with dominant high reactive {001} facets were fabricated by hydrothermal treatment of tetrabutyl titanate in hydrofluoric acid solution at 200°C for 24h. The as-prepared anatase TiO2 nanosheets show a remarkable thermal stability against phase transition up to 1100°C, which is associated with the surface fluorination. Calcination treatment accelerates the desorption of surface-bounded fluorine from the {001} facets, which results in the formation of oxygen vacancy first, and then the fusion of neighbor TiO2 nanosheets along the [001] direction (c-axis) to minimize the surface energy. High crystallization (low impurity) and oxygen vacancy are responsible for the high thermal stability of the as-prepared TiO2 nanosheets. On the other hand, heat treatment influences the photocatalytic activity as a result of the change of the textural characteristics, crystallinity degree and surface chemical states. Surprisingly, high photocatalytic activity is still remained up to 1100°C for photocatalytic oxidation decomposition of acetone in air under UV light illumination. [Copyright &y& Elsevier]

Abstract: Hierarchical porous γ-Fe2O3@SiO2@TiO2 (FST) composite microspheres with sandwich-like structure were fabricated by an effective three-step approach. Specifically, the preformed monodisperse Fe3O4 spheres were used as templates for directing the sequential deposition of SiO2 layer by modified Stöber method and subsequent TiO2 layer by vapor–thermal route. Notably, the interior black Fe3O4 templates are converted into dark-brown γ-Fe2O3 during the vapor–thermal assisted TiO2 deposition. By introducing a SiO2 layer between the γ-Fe2O3 core and TiO2 shell, while the superparamagnetic properties was remained to great extent, the photocatalytic activity towards degradation of rhodamine B (RhB) dye molecules was also significantly improved, as compared to that of the Fe3O4@TiO2 (FT) counterparts. This enhancement in photoactivity is mainly attributed to two positive effects of the interbedded SiO2 layer between the γ-Fe2O3 core and TiO2 shell. Firstly, a direct contact and electron injection from TiO2 to γ-Fe2O3 is blocked by this wide bandgap SiO2 electronic barrier, which avoids charge recombination at the interface. Secondly, a SiO2 middle layer is a good adsorbent towards dye molecules, which enhances the enrichment of pollutant dye molecules around the porous titania photoactive layer and thus the photocatalytic efficiency. Such a novel multifunctional photocatalytic integrated microspheres can effectively degrade organic pollutants and can be easily recovered by a magnet, which was reused at least five times without any appreciable reduction in photocatalytic efficiency. [Copyright &y& Elsevier]

Abstract: Mesoporous magnesium oxide microspheres were prepared by a simple precipitation and calcination method using sodium poly (4-styrenesulfonate) (PSS) as structure-directing agent. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), nitrogen adsorption–desorption isotherms and Fourier transform infrared (FTIR) spectroscopy. Adsorption of phosphate onto the as-prepared samples from aqueous solutions was investigated and discussed. The pore structure and SEM analyses indicate that MgO microspheres are composed of at least three levels of hierarchical porous organization: small mesopores (ca. 2–5nm), large mesopores (ca. 10–50nm) and macropores (50–250nm). The equilibrium adsorption data of phosphate on the as-prepared samples were analyzed by Langmuir and Freundlich models, suggesting that the Langmuir model provides the better correlation of the experimental data. The adsorption capacities for removal of phosphate were determined using the Langmuir equation and found to be 3.17 and 75.13mg/g for MgO samples prepared in pure water and in the presence of 1.0g/L PSS, respectively. Adsorption data were modeled using the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics equations. The results indicate that pseudo-second-order kinetic equation and intra-particle diffusion model can better describe the adsorption kinetics. The as-prepared mesoporous MgO microspheres are found to be effective adsorbent for the removal of phosphate from aqueous solutions as a result of their unique porous structures and high specific surface areas. [Copyright &y& Elsevier]

Abstract: Calcium carbonate microspheres with different surface structures were successfully prepared by the reaction of sodium carbonate with calcium chloride in the presence of deoxyribonucleic acid (DNA) at room temperature. The as-prepared products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis and differential scanning calorimetry (TGA–DSC) and fourier-transform infrared spectrometry (FTIR). The effects of concentration of DNA on the morphologies of the prepared CaCO3 were investigated and discussed. The results show that the surface morphology or texture of CaCO3 microspheres can easily be adjusted by varying the concentration of DNA. A critical implication was that DNA molecules could mediate the nucleation and growth of the inorganic phase and probably induce biomineralization in the biological system. This research may provide new insight into the control of morphologies of calcium carbonate and the biomimetic synthesis of novel inorganic materials. [ABSTRACT FROM AUTHOR]

Abstract: Surface-fluorinated anatase TiO2 nanosheets with dominant {001} facets were fabricated by a simple hydrothermal route in a Ti(OC4H9)4-HF-H2O mixed solution. The atomic ratios of fluorine to titanium (R F) exhibit an obvious influence on the structures and photocatalytic activity of TiO2 samples. In the presence of HF, TiO2 nanosheets can be easily obtained. With increasing R F, the relative anatase crystallinity, average crystallite size, pore size and percentage of exposed {001} facets increase, contrarily, BET specific surface areas decrease. All fluorinated TiO2 nanosheets exhibit much higher photocatalytic activity than Degussa P-25 TiO2 (P25) and pure TiO2 nanoparticles prepared in pure water due to the synergistic effect of surface fluorination and exposed {001} facets on the photoactivity of TiO2. Especially, at R F =1, the fluorinated TiO2 nanosheet exhibits the highest photocatalytic activity, and its photoactivity exceeds that of P25 by a factor of more than nine times. [Copyright &y& Elsevier]

Abstract: Ag@TiO2 core–shell nanocomposite nanowires were synthesized via a vapor-thermal method using Ag nanowires as templates and tetrabutyl titanate (TBOT) as precursors at 150°C for 10h. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption–desorption isotherms. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic decolorization of Rhodamine B (RhB) aqueous solution at ambient temperature under UV-light irradiation. The results show that the Ag@TiO2 core–shell nanowires exhibit highly efficient and recyclable photocatalytic activity for the degradation of RhB aqueous solution. Moreover, in contrast to the discrete nanoparticles, the Ag@TiO2 nanowires can be readily separated from the treated solution by natural settlement after photocatalytic reaction. [Copyright &y& Elsevier]

K and O co-doped ultrathin carbon nitride nanosheets prepared by one-step calcination with the assistance of K 2 S 2 O 8 exhibit much enhanced photocatalytic performance for CO 2 reduction under non-sacrificial and non-cocatalyst condition. [Display omitted] • The K and O atoms were co-doped into carbon nitride via one-step process by K 2 S 2 O 8. • The modified carbon nitride exbibits improved light absorption and charge separation. • The modified carbon nitride shows much enhanced CO2 photoreduction performance. Polymeric carbon nitride (CN) is a cheap and visible-light photocatalyst for potentially real application of CO 2 photoreduction into solar fuels. However, CN prepared by conventional one-step method always shows serious charge recombination and low charge mobility. Herein, we use urea as the starting material with K 2 S 2 O 8 to synthesize defect-modified ultrathin CN nanosheets. The as-prepared samples exhibit much higher photocatalytic CO 2 -reduction efficiency than the pristine CN with the production of CO and CH 4 fuels. The enhanced photocatalytic activity of modified samples is ascribed to the co-doping of K and O atoms into the CN frameworks, which promotes electron transfer from the bulk to the interface and narrows the band gap to provide a broad range of visible-light response. This work provides a simple but effective strategy to prepare defect-modified polymeric carbon nitride for various photocatalytic applications. [ABSTRACT FROM AUTHOR]

Abstract: SiO2/Al2O3 composite microspheres with SiO2 core/Al2O3 shell structure and high surface area were prepared by depositing Al2O3 colloid particles on the surface of monodispersed microporous silica microspheres using a simple electrostatic attraction and heterogeneous nucleation strategy, and then calcined at 600°C for 4h. The prepared products were characterized with differential thermal analysis and thermogravimetric analysis (DTA/TG), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption and X-ray photoelectron spectroscopy (XPS). It was found that uniform alumina coating could be deposited on the surface of silica microspheres by adjusting the pH values of the reaction solution to an optimal pH value of about 6.0. The specific surface area and pore volume of the SiO2/Al2O3 composite microspheres calcined at 600°C were 653m2 g−1 and 0.34mlg−1, respectively. [Copyright &y& Elsevier]

Abstract: Glasses for architecture must have many functions in addition to their transparency. For example, the glasses with the functions, of self-cleaning, light control, UV reduction, anti-bacterial, energy conversion, and so on, will be used in buildings in the near future. This paper reviews some results on multifunctional photoactive glasses based on multi-layer coatings containing TiO2 film and other functional coatings developed by us recently. The self-cleaning of glasses can be realized by coating the photoinduced super-hydrophilic nanoporous thin films based on TiO2 photocatalysts via sol–gel route. A new method to enhance the photocatalytic activity of TiO2 thin films direct coated on soda-lime glass was developed by treating the films in acidic solutions. The films also have good photoinduced anti-bacterial properties. The doping of a small amount of silver into the TiO2 porous film can enhance its anti-bacteria effect without UV light irradiation. The TiO2 thin films by appropriate heat-treatment can operate as self-cleaning glass in the visible light region. The UV reduction self-cleaning glasses are prepared by magnetron sputtering two layers of TiO2–CeO2 and TiO2 thin films on soda-lime glasses. The TiO2–CeO2 thin films can cut all of UV light through adjusting the ratio of TiO2 and CeO2. The TiO2/TiN/TiO2 type multi-layer coated on glass substrate can act as low-E self-cleaning glass. The potential water-repellent coating based on TiO2 is discussed finally. [Copyright &y& Elsevier]

Abstract: Preferentially oriented anatase TiO2 films were uniformly deposited on the surface of stainless steel substrate by a liquid phase deposition (LPD) method at 60°C using TiF4 and H3BO3 as precursors. The as-prepared TiO2 films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM). The photocatalytic activity of the as-prepared TiO2 films was evaluated by the photocatalytic oxidation of NO in the gaseous phase. It was found that the deposition conditions, such as the precursor concentrations (H3BO3 and TiF4), the deposition time and the pH, had an obvious effect on the formation of oriented TiO2 films. The prepared TiO2 films showed a preferential orientation in the [001] direction perpendicular to the stainless steel substrate. A formation mechanism was proposed to account for the preferential orientation and textured morphology of the TiO2 films. The photocatalytic oxidation of NO indicated that the preferentially oriented TiO2 films exhibited an obvious photocatalytic activity without high-temperature calcination. [Copyright &y& Elsevier]

Abstract: Anatase TiO2 particles were uniformly and dispersedly deposited on the surface of glass fibers by a liquid phase deposition (LPD) method from a TiF4 aqueous solution upon addition of H3BO3 at 60°C and then calcined at 60, 300 and 500°C. The photocatalytic activity of the samples was evaluated by the photocatalytic oxidation of nitrogen monoxide (NO) in the gaseous phase. It was found that calcination temperatures obviously influenced the surface morphology and photocatalytic activity of the TiO2 particles deposited on the glass fibers. At 300°C, the TiO2 samples exhibited the highest photocatalytic activity for the photocatalytic oxidation of NO and for the further conversion of NO2 (from NO2 to HNO3) due to the enhancement of crystallization of anatase TiO2 particles. At 500°C, the photocatalytic activity of the sample decreased significantly due to the dropping of many TiO2 particles from the glass fibers. Compared with the TiO2 film photocatalyst, the TiO2 particles deposited on the glass fibers exhibited a lower deactivation rate. [Copyright &y& Elsevier]

Monodispersed cubic calcium carbonate composite particles were prepared by the precipitation reaction of sodium carbonate with calcium chloride in water in the presence of polyacrylic acid (PAA) at 60–80 °C, and then characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and Differential Scanning Calorimetry-Thermogravimetry (DSC-TG). It was found from the above results that variations in the concentration of PAA and CaCO3, molar ratio of PAA to CaCO3, and pH and temperature of solution drastically changed the morphology of the as-produced CaCO3 particles, but all the products obtained consisted of calcite crystals. The optimal experimental conditions for the production of cubic calcite particles were determined. The amount of PAA in the cubic calcite composite particles was about 1.4%. [Copyright &y& Elsevier]

A new series of chalcogenide glasses in the GeS2–Ga2S3–CdS pseudoternary system was prepared in sealed silica ampoules by heating at 970 °C, and was characterized by X-ray diffraction (XRD), differential scanning calorimetry–thermogravimetry (DSC–TG) and visible-IR transmission measurements. The results show that the glass-forming region is mainly situated in the GeS2-rich domain and the amount of dissolved CdS is up to over 30 mol%. The glasses have relatively high glass transition temperatures (Tg=375–436 °C) and good thermal stabilities. The most stable glass with the composition of 90GeS2–5Ga2S3–5CdS (in mol%) has a broad region of transmission from 0.46 to 10.5 μm and good chemical stability in normal air conditions. These glasses may be widely used in the field of optoelectronics. [Copyright &y& Elsevier]

[Display omitted] It is imperative to seek for novel materials with pronounced gas sensing performance towards triethylamine for the sake of human health. Herein, we successfully fabricate an outstanding triethylamine sensor based on CdS/ZnO composite with 0D/2D structure, which are prepared by in-situ growth of CdS quantum dots on ultra-thin ZnO nanosheets. The ratios between the two ingredients are adjusted and their effect is evaluated. The optimal sample exhibits the lowest operating temperature of 200 °C, the highest response value of ~20 and the fastest response time of 2 s. Besides, it also has the virtues of durable stability, excellent selectivity and superior anti-interference ability. The mechanism behind the aforementioned intriguing performance is investigated by X-ray photoelectron spectroscopy, Kelvin probe and density function theory (DFT) simulation. All the results verify that the enhanced gas sensing properties are derived from splendid 0D/2D structure, n - n heterojunction and large specific surface area. Additionally, this study opens an avenue for designing sensors with 0D/2D structure. [ABSTRACT FROM AUTHOR]

Photocatalytic production of H2O2 from water and atmospheric oxygen has been recognized as a green and sustainable chemical process, due to the abundance of raw materials and sustainable solar energy. Herein, flower-like hierarchical ZnO microspheres were prepared by hydrothermal method followed by calcination at different temperatures, and their photocatalytic performance in H2O2 production was examined under simulated sunlight irradiation. The calcination temperature plays a vital role in the structure, morphology, and surface area of the final ZnO products as well as their optical and electrochemical properties, which are determining factors in their photocatalytic activity. The ZnO calcined at 300 °C (Zn-300) exhibits the highest activity and optimal stability, showing productivity of 2793 μmol l−1 within 60 min of irradiation, which was 6.5 times higher than that of uncalcined ZnO precursor. The remarkable photocatalytic activity is attributed to enhanced light utilization, large surface area, abundant exposed active sites, improved separation efficiency, and prolonged carrier lifespan. Moreover, the results from cycling experiments indicate the as-prepared ZnO samples exhibit good stability and long-time performance. This work provides useful information for the preparation of hierarchical ZnO photocatalysts. [ABSTRACT FROM AUTHOR]