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Severe poisonousness and prolonged instability existing in organic‐inorganic lead‐based perovskite are two matters seriously hindering its potential future application in photocatalysis. Therefore, it is particularly important to explore ecology‐friendly, air‐stable and highly active metal‐halide perovskites. Herein, a new and stable lead‐free perovskite Cs2SnBr6 decorated with reduced graphene oxide (rGO), is synthesized and employed in the photocatalytic organic conversion. The as‐prepared Cs2SnBr6 is ultrastable, exhibiting no clear changes after being placed in the air for six months. The Cs2SnBr6/rGO composite shows excellent photocatalytic activity in photo‐driven‐oxidation of 5‐hydroxymethylfurfural (HMF) to high value enclosed 2,5‐diformylfuran (DFF), achieving>99.5 % conversion of HMF and 88 % DFF selectivity in the presence of green oxidant O2. Comprehensive characterizations disclose a multistep reaction mechanism, demonstrating that the molecular oxygen, photogenerated carriers, ⋅O2− and 1O2 altogether synergistically participate in the effective photo‐driven conversion of HMF to DFF. This work expands the material gallery towards selective organic conversion and environmentally friendly perovskite options for photocatalytic application. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen peroxide (H2O2) production on BiVO4 photocatalysts using water and oxygen as raw materials is a green and sustainable process. However, the photocatalytic efficiency of pristine BiVO4 is limited by severe charge recombination. In this work, rare earth element Yttrium (Y) doped BiVO4 photocatalysts were fabricated by the hydrothermal method. In the photocatalytic H2O2 production experiment, the optimized Y‐doped BiVO4 photocatalyst produced 114 μmol g−1 h−1 of H2O2 under simulated sunlight (AM1.5) irradiation, which is four times higher than production activity of pure BiVO4 (26 μmol g−1 h−1). Density functional theory (DFT) calculation revealed that Y doping can enhance oxygen adsorption on the BiVO4 photocatalyst surface. Mechanistic investigations suggest that the doping process induces the in situ formation of monoclinic/tetragonal BiVO4 heterojunction, which further promotes the photogenerated carriers separation efficiency. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen peroxide (H2O2) production on BiVO4 photocatalysts using water and oxygen as raw materials is a green and sustainable process. However, the photocatalytic efficiency of pristine BiVO4 is limited by severe charge recombination. In this work, rare earth element Yttrium (Y) doped BiVO4 photocatalysts were fabricated by the hydrothermal method. In the photocatalytic H2O2 production experiment, the optimized Y‐doped BiVO4 photocatalyst produced 114 μmol g−1 h−1 of H2O2 under simulated sunlight (AM1.5) irradiation, which is four times higher than production activity of pure BiVO4 (26 μmol g−1 h−1). Density functional theory (DFT) calculation revealed that Y doping can enhance oxygen adsorption on the BiVO4 photocatalyst surface. Mechanistic investigations suggest that the doping process induces the in situ formation of monoclinic/tetragonal BiVO4 heterojunction, which further promotes the photogenerated carriers separation efficiency. [ABSTRACT FROM AUTHOR]

Overall water splitting to generate H2 and O2 is vital in solving energy problem. It is still a great challenge to seek efficient visible light photocatalyst to realize overall water splitting. In this work, the tetragonal zircon BiVO4 is prepared by epitaxial growth on FTO substrate and its overall water splitting reaction is studied. Under the influence of epitaxial strain, the conduction band position shifts negatively and beyond H+/H2 reduction potential (0 V vs NHE), which enables it to possess the photocatalytic hydrogen evolution activity. After loading cocatalysts, the overall water splitting (λ > 400 nm) is realized (H2: ≈65.7 µmol g−1 h−1, O2: ≈32.6 µmol g−1 h−1), and the value of solar hydrogen conversion efficiency is 0.012%. The single‐particle photoluminescence (PL) spectra and PL decay kinetics tests demonstrate the cocatalysts are beneficial to the separation and transfer of carriers. The new strategy of adjusting the band structure by strain is provided. [ABSTRACT FROM AUTHOR]

Overall water splitting to generate H2 and O2 is vital in solving energy problem. It is still a great challenge to seek efficient visible light photocatalyst to realize overall water splitting. In this work, the tetragonal zircon BiVO4 is prepared by epitaxial growth on FTO substrate and its overall water splitting reaction is studied. Under the influence of epitaxial strain, the conduction band position shifts negatively and beyond H+/H2 reduction potential (0 V vs NHE), which enables it to possess the photocatalytic hydrogen evolution activity. After loading cocatalysts, the overall water splitting (λ > 400 nm) is realized (H2: ≈65.7 µmol g−1 h−1, O2: ≈32.6 µmol g−1 h−1), and the value of solar hydrogen conversion efficiency is 0.012%. The single‐particle photoluminescence (PL) spectra and PL decay kinetics tests demonstrate the cocatalysts are beneficial to the separation and transfer of carriers. The new strategy of adjusting the band structure by strain is provided. [ABSTRACT FROM AUTHOR]

Severe poisonousness and prolonged instability existing in organic-inorganic lead-based perovskite are two matters seriously hindering its potential future application in photocatalysis. Therefore, it is particularly important to explore ecology-friendly, air-stable and highly active metal-halide perovskites. Herein, a new and stable lead-free perovskite Cs 2 SnBr 6 decorated with reduced graphene oxide (rGO), is synthesized and employed in the photocatalytic organic conversion. The as-prepared Cs 2 SnBr 6 is ultrastable, exhibiting no clear changes after being placed in the air for six months. The Cs 2 SnBr 6 /rGO composite shows excellent photocatalytic activity in photo-driven-oxidation of 5-hydroxymethylfurfural (HMF) to high value enclosed 2,5-diformylfuran (DFF), achieving>99.5 % conversion of HMF and 88 % DFF selectivity in the presence of green oxidant O 2 . Comprehensive characterizations disclose a multistep reaction mechanism, demonstrating that the molecular oxygen, photogenerated carriers, ⋅O 2 - and 1 O 2 altogether synergistically participate in the effective photo-driven conversion of HMF to DFF. This work expands the material gallery towards selective organic conversion and environmentally friendly perovskite options for photocatalytic application., (© 2023 Wiley-VCH GmbH.)

Photocatalytic hydrogen peroxide (H 2 O 2 ) production on BiVO 4 photocatalysts using water and oxygen as raw materials is a green and sustainable process. However, the photocatalytic efficiency of pristine BiVO 4 is limited by severe charge recombination. In this work, rare earth element Yttrium (Y) doped BiVO 4 photocatalysts were fabricated by the hydrothermal method. In the photocatalytic H 2 O 2 production experiment, the optimized Y-doped BiVO 4 photocatalyst produced 114 μmol g -1  h -1 of H 2 O 2 under simulated sunlight (AM1.5) irradiation, which is four times higher than production activity of pure BiVO 4 (26 μmol g -1  h -1 ). Density functional theory (DFT) calculation revealed that Y doping can enhance oxygen adsorption on the BiVO 4 photocatalyst surface. Mechanistic investigations suggest that the doping process induces the in situ formation of monoclinic/tetragonal BiVO 4 heterojunction, which further promotes the photogenerated carriers separation efficiency., (© 2023 Wiley-VCH GmbH.)

Fluorinated graphene (FG) possess distinctively novel properties different from graphene and is suitable for many biomedical applications. However, the hydrophobic nature and inert properties of FG limit its further application as a biological material. Here we show the preparation of nano-sized FG (ca. 60 nm) that exhibits high NIR absorbance for photothermal therapy. In order to make it stable in physiological solutions, the FG is enriched with oxygen and followed by covalent binding with chitosan as a novel pH-responsive nanocarrier. Furthermore, controlled loading of two anticancer drugs, doxorubicin (DOX) and camptothecin (CPT) has been realized and the functionalized ultrasmall FG shows remarkably high cytotoxicity toward Hela cancer cells compared to that loaded with either CPT or DOX only. This work established nano-sized FG as a novel photothermal agent due to its small size and can be used a stimulus-responsive nanocarrier for mixed drug delivery and combined therapy., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)