单层MoS<sub>2</sub>在合金化及应力调控下光催化裂解水产氢的理论研究

单层MoS₂在合金化及应力调控下光催化裂解水产氢的理论研究

摘要: 基于密度泛函的第一性能原理计算方法研究了单层MoS₂分别与MoSe₂、MoTe₂、WS₂进行合金化, 以及加入2%应力条件下, 对光催化裂解水性能的影响。计算结果表明, 单层MoS₂通过与MoSe₂、MoTe₂、MoWS₂进行合金化, 并施加压应力两种手段进行调控, 可使带隙变大的同时, 提高CBM(conduction band minimum)带边位置, 从而提高光催化分解水的效率。通过能带和态密度的计算表明, 合金元素原子形成的不是孤立能级而是能带, 对载流子寿命影响小。

Abstract: Based on the density functional theory, the photocatalytic water splitting reaction has been studied over the monolayer MoS₂ alloying with MoSe₂, MoTe₂ and WS₂ under stress condition. The calculated results show that the monolayer MoS₂ alloyed with MoSe₂, MoTe₂ and MoWS₂ under the compressive stress condition can increase the band gap and improve the position of CBM (conduction band minimum) band edge to enhance the efficiency of photocatalytic water splitting. The calculated energy band and density of states show that the alloy elements form energy band instead of isolated energy level, which has little effect on carrier life.