Hu Jisong, Liu Jie, Chen Zhangze, Ma Xinguo, Liu Yang, Wang Shiqi, Liu Zhifeng, Huang Chuyun
School of Science, Hubei University of Technology, Wuhan 430068, China.
Phys Chem Chem Phys. 2020 Oct 15;22(39):22349-22356. doi: 10.1039/d0cp03241g.
An understanding of the high photocatalytic performance reported for MoS2/BiOI nanocomposite is far from satisfactory. Here, the interfacial interaction and electronic properties of a MoS2/BiOI heterostructure were investigated systematically for the first time by first-principle calculations incorporating a semi-empirical dispersion-correction scheme. Our results confirm the reasonable existence of van der Waals interactions and a favorable Z-scheme mechanism, based on the typical interfacial cohesive energy and the energy level lineup at the interface. Analyzing the charge density differences and work functions, the built-in electric field is formed along the direction from MoS2 to BiOI after the interface equilibrium, and facilitates the separation of photoinduced electron-hole pairs in the interface. Additionally, it can be inferred that the incorporation of MoS2 into BiOI increases the carrier mobility and improves light harvesting, in agreement with the previously reported experimental data. Our work provides an insight into the mechanism of the enhanced visible-light photocatalytic activity of a MoS2/BiOI heterostructure, and helps to design other new heterostructure combinations.
对于二硫化钼/碘氧化铋纳米复合材料所报道的高光催化性能，目前的理解还远不能令人满意。在此，首次通过结合半经验色散校正方案的第一性原理计算，系统地研究了二硫化钼/碘氧化铋异质结构的界面相互作用和电子性质。基于典型的界面结合能和界面处的能级排列，我们的结果证实了范德华相互作用的合理存在和良好的Z型机制。通过分析电荷密度差和功函数，界面平衡后沿二硫化钼到碘氧化铋的方向形成了内建电场，促进了界面处光生电子 - 空穴对的分离。此外，可以推断将二硫化钼掺入碘氧化铋中会增加载流子迁移率并改善光捕获，这与先前报道的实验数据一致。我们的工作深入了解了二硫化钼/碘氧化铋异质结构增强可见光光催化活性的机制，并有助于设计其他新型异质结构组合。
