Photocatalytic H 2 evolution provides an upcoming route for the production of clean fuel via the conversion of solar energy. TiO 2 , as a potential semiconductor material, is restricted by its faint absorption of visible light, thus limiting its application in water splitting. Herein, high visible light responsive ZnIn 2 S 4 /TiO 2-x nanotube arrays for photocatalytic hydrogen evolution were fabricated by two-step reaction. ZnIn 2 S 4 /TiO 2-x nanotube arrays exhibited the photo response from UV to visible-light region due to the introduction of oxygen vacancies and visible-light driven ZnIn 2 S 4 . Moreover, the heterojunction improved the separation of photogenerated carriers and boosted the electron transfer from ZnIn 2 S 4 to TiO 2-x , thereby increasing the longevity of active electrons, which enhanced the photocatalytic activity for hydrogen evolution. An outstanding H 2 production rate of 581.1 μmol h −1 g −1 was obtained and an apparent quantum yield (AQY) up to ∼ 1.42% was achieved. This work demonstrates that the defect-induced bandgap engineering of semiconductor photocatalysts is a potential way to extend the optical absorption property of TiO 2 to visible light even or NIR and enhance the photocatalytic activity.
Novel Z-scheme ZnIn 2 S 4 /TiO 2-x photocatalyst was successfully fabricated through self-sacrificing template-chemical bath deposition combined with a NaBH 4 reduction method for the first time. It was found that ZnIn 2 S 4 /TiO 2-x exhibited high-efficient visible-light photocatalytic RhB degradation of 91 % within 40 min, which was almost 45.5, 1.2, and 6.1 times better than that of TiO 2 , ZnIn 2 S 4 /TiO 2 , and TiO 2-x , respectively. Moreover, an obscure change in catalytic activity can be observed after five recycles. The excellent photocatalytic performance can be attributed to the synergistic effect of Ov, ZnIn 2 S 4 , and MOF-derived TiO 2 , which extend the visible-light photoresponse range and promote the separation of photo-generated charge carriers.
Jiaqing Liu,Jun Wan,Lin Liu,Weijie Yang,Jingxiang Low,Xiaoming Gao,Feng Fu
Aiming to the unwanted photocatalytic hydrogen production systems using sacrifice agents, a well-design S-scheme O-ZnIn 2 S 4 /TiO 2- x heterojunction was fabricated to realize photocatalytic hydrogen production via water reduction coupled with organic oxidative dehydrogenation. As supported by DFT calculations and experimental analysis, owing to the synergistic effect of oxygen defect and doping engineering, a tailored energy band structure alignment with higher redox potentials and larger Fermi level potential difference are achieved, resulting in more efficient S-scheme interface charge transfer and separation efficiency, thus improving the photocatalytic activity of O-ZnIn 2 S 4 /TiO 2- x . The optimal O-ZnIn 2 S 4 /TiO 2- x photocatalyst shows remarkable H 2 and benzaldehyde production rate of 2584.9 μmol g -1 h −1 and 2880.5 μmol g -1 h −1 under visible light, which are 52.5 and 66.4 times as high as those over blank TiO 2 . Interestingly, this coupled reaction system also displays superior H 2 evolution activity compared to sacrificial reagent systems of Na 2 SO 3 /Na 2 S and triethanolamine. Further quenching and EPR experiments reveal that both water and organic molecules provide protons for H 2 production.
危险品化学品经营许可证（带存储）