Tian Sheng, Ding Yu-Feng, Cai Meng-Qiu, Chen Lang, Au Chak-Tong, Yin Shuang-Feng
Advanced Catalytic Engineering Research Center of the Ministry of Education, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Provincial Hunan Key Laboratory for Cost-effective Utilization of Fossil Fuel Aimed at Reducing Carbon-dioxide Emissions, Hunan University, Changsha 410082, Hunan Province, P. R. China.
Phys Chem Chem Phys. 2021 Sep 7;23(33):17894-17903. doi: 10.1039/d1cp02124a. Epub 2021 Aug 11.
Bismuth oxyhalides (BiOX), as a typical photocatalytic material, have attracted much attention due to their unique layered structure, non-toxicity and excellent stability. However, the photocatalytic performance of BiOX is limited by their weak light absorption ability and rapid recombination of photo-generated carriers. In the present work, first-principles calculations have been performed to comprehensively explore the structural, electronic and optical properties of black phosphorus (BP)/BiOX (X = Cl, Br, I) heterostructures, revealing the inherent reasons for their enhanced photocatalytic performance. By combining band structures and work function analysis, the migration paths of photo-generated electrons and holes are obtained, proving a direct Z-scheme photocatalytic mechanism in BP/BiOX heterostructures. Moreover, the BP/BiOX heterostructures have decent band edge positions, which are suitable for photocatalytic overall water splitting. Compared with single BiOX, the light absorption performance of BP/BiOX heterostructures is significantly improved, in which BP/BiOI exhibits the highest optical absorption coefficient among the BP/BiOX heterostructures. Meanwhile, the better carrier migration performance of the BP/BiOX heterostructures is attributed to the reduction in effective mass. The present work offers theoretical insight into the application of BP/BiOX heterostructures as prominent photocatalysts for water splitting.
卤氧化铋（BiOX）作为一种典型的光催化材料，因其独特的层状结构、无毒且稳定性优异而备受关注。然而，BiOX的光催化性能受其光吸收能力弱和光生载流子快速复合的限制。在本工作中，进行了第一性原理计算以全面探究黑磷（BP）/BiOX（X = Cl、Br、I）异质结构的结构、电子和光学性质，揭示其光催化性能增强的内在原因。通过结合能带结构和功函数分析，获得了光生电子和空穴的迁移路径，证明了BP/BiOX异质结构中存在直接Z型光催化机制。此外，BP/BiOX异质结构具有合适的能带边缘位置，适用于光催化全分解水。与单一BiOX相比，BP/BiOX异质结构的光吸收性能显著提高，其中BP/BiOI在BP/BiOX异质结构中表现出最高的光吸收系数。同时，BP/BiOX异质结构更好的载流子迁移性能归因于有效质量的降低。本工作为BP/BiOX异质结构作为突出的光催化分解水催化剂的应用提供了理论见解。
