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Series of Bi2MoO6/NiAl-LDH hetero-junction photocatalysts were synthesized by a two-step hydrothermal method with a self-assembled process. It indicated that the in-situ intercalated NiAl-LDH showed a tight contact with Bi2MoO6 layers and thus exhibited the rapid transfer of photogenerated electrons on the interface. The photocatalytic performance was evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. The resulted Bi2MoO6/NiAl-LDH sample showed a higher visible-light photocatalytic activity for the degradation of RhB than any single component. The optimal LDH content in Bi2MoO6/NiAl-LDH is 15% with the degradation efficiency for more than 90% during 60 min. The excessive amount of NiAl-LDH in Bi2MoO6/NiAl-LDH could reduce the light absorption efficiency of Bi2MoO6 and thus affected the generation of photoinduced electron-hole pairs. The enhanced photocatalytic activity and stability of Bi2MoO6/NiAl-LDH was attributed to the synergistic effects of the introduction of narrow band-gap NiAl-LDH and the construction of layered hetero-junction. Our synthetic method of self-assembly sheets has certain guided significance for the synthesis and application of other photocatalysts. [ABSTRACT FROM AUTHOR]

Ag10Si4O13 photocatalyst was prepared by using silver nitrate as raw material-anhydrous ethanol as solvent and silica sol as complexing agent. The precursor was obtained by sol-gel method. The precursor was calcined in a tube furnace. Preparation of Ag10Si4O13photocatalytic coating based on silica sol/potassium silicate solution and fluorocarbon emulsion. The catalyst was characterized by XRD,SEMUV,Vis DRS and other means, and the performance of the coating and the effect of NO removal by the coating were tested. The results show that the morphology of Ag10Si4O13 is a columnar structure; the light absorption edge is 640 nm-corresponding to the band gap of 2.02 eV. The photocatalytic test results showed that the removal rate of NO was 68.8% for the Ag10Si4O13 photocatalytic coating with a mass content of 1.0% when the xenon lamp was irradiated for 90 min. [ABSTRACT FROM AUTHOR]

CoAl-layered double hydroxide nanosheets (CoAl-NSs) could serve as an active matrix to effectively anchor amorphous MoSx nanoparticles with high dispersion and the formation of an additional active “CoMoS” phase. The resulting CoAl-NSs/MoSx catalyst showed 13 times higher H2 evolution activity than free MoSx nanoparticles from an erythrosin B–triethanolamine (ErB–TEOA) system under visible light. [ABSTRACT FROM AUTHOR]

Thiomolybdate [Mo3S13]2− nanoclusters, as a molecular mimic of MoS2 edge sites, showed high efficiency in catalyzing photochemical H2 evolution from a molecular system of Ru(bpy)3Cl2–ascorbic acid (H2A) under visible light irradiation (≥420 nm), providing a turnover number of 1570 and an initial turnover frequency of 335 h−1 for H2 evolution based on the [Mo3S13]2− catalyst. [ABSTRACT FROM AUTHOR]

Abstract: A Ni@NiO core/shell cluster was fabricated on TiO2 surface (Ni@NiO/TiO2) and its roles on surface electron transfer and the enhancement on hydrogen evolution under visible light irradiation were investigated. For a comparison, the Ni/TiO2 and NiO/TiO2 catalysts were fabricated, respectively. By photosensitization using Eosin Y as an antenna molecule, (1.6 wt%)Ni@NiO/TiO2 exhibited the highest activity (364.1 μmol h−1) in comparison with (1.6 wt%)Ni/TiO2 and (1.6 wt%)NiO/TiO2 and the corresponding apparent quantum efficiency reached 28.6% at 460 nm. The photoluminescence spectra and photoelectrochemical characterization results confirmed that the Ni@NiO core/shell structure could promote the photogenerated electrons transferring from TiO2 conduction band to Ni@NiO clusters, resulting in the quicker separation of electron–hole pairs. In addition, part of NiO shell can be reduced into metallic Ni during the photoreaction and vice versa. Cyclic voltammogram characterization verified that the transformation between Ni and NiO was a dynamic balance process, which can not only provide reacting channels for electrons and protons but also ensure the photocatalytic hydrogen evolution proceeding continuously. This study discloses structure-dependent effect of non-noble metal cocatalyst on semiconductor photocatalysts in photocatalytic water reduction, and gives an insight into designing high-efficient non-noble metal/semiconductor hybrid photocatalysts. [Copyright &y& Elsevier]

Abstract: In this study, Au/TiO2 samples with different exposed facets ({100}, {100/111}, and {111}) of Au were employed as catalysts for the examination of facet-dependent catalytic activity toward photocatalytic hydrogen evolution from water. By photosensitized using Eosin Y as antenna molecule, Au/TiO2 series photocatalysts exhibited different photocatalytic hydrogen evolution performances under visible light irradiation. Au{111}/TiO2 photocatalyst presented the highest photocatalytic hydrogen generation activity among Au/TiO2 series samples. As evidenced by photoluminescence spectra, photocurrent, electrochemical impedance spectra, and Mott–Schottky characterizations, the difference in photocatalytic activities resulted from the different electron transfer rates from the conduction band of TiO2 to Au nanoparticles. Au nanoparticles with exposed {111} facets were more effective in trapping electrons due to their higher Fermi level. In addition, the apparent activation energy of Au{111}/TiO2 sample was the lowest, resulted from the biggest uncoordinated numbers of Au atoms on Au{111} nanoparticles, which was favor in forming the hydrogen–metal bond. This study discloses the facet-dependent effect of noble-metal cocatalyst on semiconductor photocatalysts in photocatalytic water reduction, and will give an insight into design and synthesis of high-efficient noble metal/semiconductor hybrid photocatalysts. [Copyright &y& Elsevier]

An interfacial structure is crucial to the photoinduced electron transport for a heterostructure photocatalyst. Constructing an interfacial electron channel with an optimized interfacial structure can efficiently improve the electron-transfer efficiency. Herein, the rapid electron-transfer channels were built up in a Cu 2 O/SrFe 0.5 Ta 0.5 O 3 heterojunction (Cu 2 O/SFTO) based on the selective bonding effect of heterologous surface oxygen vacancies in the SFTO component. The heterologous surface oxygen vacancies, namely, V O-Fe and V O-Ta , respectively, adjacent to Fe and Ta atoms, were introduced into fabricating the Z-scheme Cu 2 O/SFTO heterojunction. Compared with sample Cu 2 O/SFTO with V O-Fe , the photocatalytic NO removal efficiency of sample Cu 2 O/SFTO with V O-Fe and V O-Ta was increased by 22.5%. The enhanced photocatalytic performance originated from the selective bonding effect of heterologous V O-Fe and V O-Ta on the interfacial electron-separating and -transfer efficiency. V O-Fe is the main body to construct the interfacial electron-transfer channels by forming interfacial Fe-O-Cu(I) bonds, which causes lattice distortion at the interface, and V O-Ta can optimize the structure of interfacial channels by balancing the electron density of SFTO to control the average space of the interface transition zone. This research provides a new cognitive perspective for constructing double perovskite oxide-based heterostructure photocatalysts.