Photocatalytic water splitting to generate hydrogen has attracted great attention due to its potential for conversion and storage of solar energy. To obtain high efficiency of water splitting under solar irradiation, the catalyst should have good enough absorption in the visible region, excellent charge transfer ability, and satisfied stability during the photoreaction. Herein, the significant absorption promotion of the catalyst to a longer wavelength is achieved by simultaneously in situ selenylation and phosphorization of Ga₂O₃. The formation of narrow-bandgap Ga₂Se₃ and GaP layers makes the catalyst absorb visible light up to 640 from 282 nm. In addition, by embedding a TiO₂ transition layer between Ga₂O₃ and Ga₂Se₃, better crystal match in the catalyst is accomplished, which leads to better structural stability and the formation of better charge transfer route. Compared with GaP/Ga₂O₃/Ga₂Se₃, the GaP/TiO₂/Ga₂O₃/TiO₂/Ga₂Se₃ photocatalyst exhibits a much higher photocatalytic H₂ evolution activity and achieves a higher apparent quantum efficiency (≈4% at 430 nm). Moreover, the TiO₂ transition layer also reduces the crystal mismatch between GaP and Ga₂O₃. Herein, the advantage of utilizing the transition layer in multijunction photocatalyst to increase the photocatalytic activity and strengthen the stability of the assembled catalyst for overall water splitting is demonstrated.

中文翻译：

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通过在 GaP/Ga2O3/Ga2Se3 多结光催化剂中嵌入 TiO2 过渡层提高光收集和整体水分解效率

光催化分解水产生氢气因其在太阳能转换和储存方面的潜力而引起了人们的极大关注。为了在太阳辐射下获得高效率的水分解，催化剂应在可见光区具有足够好的吸收性、优异的电荷转移能力和光反应过程中令人满意的稳定性。在此，催化剂对更长波长的显着吸收促进是通过Ga ₂ O _{3 的}同时原位硒化和磷化实现的。窄带隙Ga ₂ Se ₃和GaP 层的形成使催化剂从282 nm 吸收高达640 的可见光。此外，通过嵌入的TiO ₂嘎之间过渡层₂ O ₃和Ga ₂ Se ₃，在催化剂中实现了更好的晶体匹配，这导致更好的结构稳定性和更好的电荷转移路线的形成。用的GaP / GA相比₂ ö ₃ / GA ₂硒₃，在GaP /二氧化钛₂ / GA ₂ ö ₃ /二氧化钛₂ / GA ₂硒₃光催化剂表现出高得多的光催化ħ ₂演化的活性和实现了更高的表观量子效率（ ≈4% 在 430 nm）。此外，TiO ₂过渡层还减少了 GaP 和 Ga ₂ O ₃之间的晶体失配。在此，证明了利用多结光催化剂中的过渡层来提高光催化活性并增强组装催化剂对整体水分解的稳定性的优势。