光催化裂解水产氢在解决全球环境与能源问题方面表现出较大潜力，构建复合催化剂可有效提高催化效率，是该领域的研究热点之一。CdS/MS2(M=Mo，W)是一种高效的复合催化剂，然而MS2提高CdS催化效率的物理机制尚不清晰，相关实验结果也由于表面/界面结构的差别而存在争议。本项目拟开展第一性原理计算，研究不同取向CdS/MS2的电子结构，分析界面带阶，揭示其对界面取向的依赖关系以及光激发载流子在不同界面的迁移方向，阐明MS2自旋轨道耦合效应与CdS(001)本征极化电场对带阶的影响；进一步通过基于含时密度泛函理论的分子动力学模拟，探究CdS/MS2中光激发载流子的界面迁移动力学行为，揭示基态电子结构、声子-载流子散射和载流子-载流子散射在载流子迁移过程中的作用，建立载流子半导体界面迁移的动力学物理图像；最终给出MS2提高CdS催化效率的物理机制，并为实验制备更高效的复合催化剂提供理论参考。

Photocatalytic water splitting is a promising solution to global energy and environmental problems. The use of heterogeneous catalysts could enhance hydrogen generation considerably and have attracted much attention. MS2 (M=Mo, W) can greatly enhance the activity of CdS when it is used as the co-catalyst. However, the physical mechanism remains not clear yet, and related experimental results are also controversial due to the complexity of surface/interface. In this project, we will study the electronic structures of CdS/MS2 interfaces with different orientations and their carrier dynamics at interface region through first-principles calculations and time-dependent density functional theory along with molecular dynamics simulations. We aim to clarify the transfer direction of carrier at interface by analyzing the band alignment, demonstrate the effect of spin-orbit coupling of MS2 on the band offset, and reveal the origin of intrinsic internal electric field at CdS(001) surface and its role (promoting or inhibiting) when carrier transferring at interface. By simulating the time evolution of carrier location at real space, we will reveal the role of ground-state electronic structure, phonon-carrier scattering and carrier-carrier scattering at energy relaxation process, and construct a physical picture of carrier transfer at semiconductor interface. Our work will unveil the physical mechanism and provide a theoretical basis for guiding the experimentalist to prepare more efficient composite catalysts.