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Here, we successfully prepared Ba2Bi3Ta2O11Cl via a simple one-step molten salt method and adjusted its crystal morphology and structure, based on which the O2-evolving activity was significantly improved. In addition, W doping promotes the charge separation efficiency, lowers the energy barrier for water oxidation reaction, and thus improves the activity. Finally, the optimized W-doped sample after molten salt treatment shows the best O2 production activity (55 μmol h−1) without loading any cocatalyst, which is 6 times higher than that of pristine Ba2Bi3Ta2O11Cl and 2 times higher than that of the undoped Ba2Bi3Ta2O11Cl treated with molten salt, respectively. [ABSTRACT FROM AUTHOR]

Developing mixed‐anion semiconductors for solar fuel production has inspired extensive interest, but the nitrohalide‐based photocatalyst is still in shortage. Here we report a layered nitro‐halide β‐ZrNBr with a narrow band gap of ca. 2.3 eV and low defect density to exhibit multifunctionalities for photocatalytic water reduction, water oxidation and CO2 reduction under visible‐light irradiation. As confirmed by the results of electron paramagnetic resonance (EPR) and density functional theory (DFT) calculations, the formation of anion vacancies in the nitro‐halide photocatalyst was inhibited due to its relatively high formation energy. Furthermore, performance of β‐ZrNBr can be effectively promoted by a simple exfoliation into nanosheets to shorten the carrier transfer distance as well as to promote charge separation. Our work extends the territory of functional photocatalysts into the nitro‐halide, which opens a new avenue for fabricating efficient artificial photosynthesis. [ABSTRACT FROM AUTHOR]

To efficiently utilize solar energy and catalyze the water splitting reaction under visible-light, a novel strategy of first nitridation and subsequent calcination post-treatment methods is developed to prepare N,F-codoped TiO2 (TNOF) photocatalysts in this work. The prepared sample exhibits obvious band-to-band absorption with an edge up to ca. 580 nm. After calcinating the nitrided sample at low temperature in air, the Ti3+ defects, which could trap photo-generated electrons during photocatalysis, would be significantly reduced. Under visible-light irradiation, the TNOF photocatalyst presents excellent water oxidation performance in AgNO3 aqueous solution or Fe3+ reversible electron acceptor. Based on the obtained TNOF sample, an efficient Z-scheme water overall splitting system is successfully constructed combining with a known Ru/SrTiO3:Rh H2-evolution photocatalyst. Moreover, the TNOF photocatalysts also show good visible-light-driven water reduction and CO2 reduction activities. This work presents a novel strategy to prepare nitrogen-incorporated oxide photocatalysts with low defect concentrations for photocatalytic applications. [ABSTRACT FROM AUTHOR]

The development of visible-light-responsive photocatalysts for promoting solar-driven oxygen (O2) production from water splitting is a potentially attractive but still a challenging scheme. In the present work, a (111)-type layered perovskite oxynitride, Sr5Nb4O15−xNx, was synthesized via the nitridation treatment of the disk-like oxide precursor under the ammonia flow, which was fabricated using a flux method. The homogeneous dispersion of nitrogen (N) dopant in N-doped Sr5Nb4O15 was ascertained by energy-dispersive X-ray spectroscopy characterization, and the Sr5Nb4O15−xNx was found to be a direct semiconductor with a light absorption edge of approximately 640 nm. Density functional theory investigation implies that the hybridization between the outmost N 2p orbitals and O 2p orbitals upshifts the original valence band maximum of Sr5Nb4O15 and endows its visible-light-responsive characteristics. Loading with cobalt oxide (CoOx) as cocatalyst, the as-prepared Sr5Nb4O15−xNx exhibited an enhanced photocatalytic O2 evolution activity from water splitting under visible-light illumination (λ > 420 nm). Moreover, another homogeneous N-doped layered perovskite-type niobium (Nb)-based oxynitride, Ba5Nb4O15−xNx, was also developed and investigated for the visible-light-actuated O2 production, highlighting the versatility of the present approach for exploring novel visible-light-responsive photocatalysts. [ABSTRACT FROM AUTHOR]

A pyrochlore-structural oxynitride Nd2Ta2O5N2 with a visible light absorption edge of ca. 620 nm was explored for photocatalytic water splitting. Dual functions of Nd2Ta2O5N2 were confirmed by proton reduction and water oxidation half-reactions through separately loading Pt or CoOx as a cocatalyst in the presence of the corresponding sacrificial reagent. Finally, the platinum modified sample (Pt/Nd2Ta2O5N2) was prepared and employed as the H2-evolving photocatalyst to fabricate an effective photocatalytic Z-scheme overall water splitting together with PtOx/WO3 as the O2-evolving photocatalyst and IO3−/I− as shuttle ions under visible light irradiation. [ABSTRACT FROM AUTHOR]

Inorganic perovskite solar cells (PSCs) have witnessed extraordinary advances owing to their prominent stability against thermal aging. However, they suffer from a phase transition from black phase to yellow phase under ambient conditions and serious energy losses relative to the optical bandgap. Herein, urea (Ur) and methyl‐substituted urea (Me‐Ur) additives are used to modulate the lattice structure and crystallinity of the CsPbI2Br, facilitating phase stability and high device performance. The Me‐Ur can attenuate the strong hydrogen bonding networks in the Ur, which leads to stronger coordination of the carbonyl group with undercoordinated Pb2+, more efficiently passivating the defect states and suppressing the lattice distortion of the [PbI6]4− octahedra in the CsPbI2Br perovskite. Consequently, a champion power conversion efficiency of 16.5% with an open‐circuit voltage up to 1.33 V is obtained for the CsPbI2Br+Me‐Ur‐based PSCs, accompanied by enhanced stability under continuous illumination at a temperature of 45 ± 5 °C. These results emphasize the importance of regulating the lattice distortion by the urea derivative to implement efficient and stable inorganic CsPbI2Br PSCs. [ABSTRACT FROM AUTHOR]