The electronic structures of two dimensional (2D) CdS/ZnO heterostructure (CdZnHT) consisting of CdS singlelayer (SL) and ZnO SL are explored based on hybrid density functional calculation. The negative interface formation energies suggest the formation of CdZnHT is exothermic. The bandgap of CdZnHT is favorable for absorbing visible light, and the decent band edge position makes it thermodynamically feasible for spontaneous generation of oxygen and hydrogen. The formed electric field across the interface induced by charge transfer will reduce photogenerated carrier recombination and promote carrier migration. Particularly, CdZnHT is a type-II heterostructure. Oxygen generation takes place at ZnO layer and hydrogen production occurs at CdS layer, which will also promote the effective separation and migration of phogogenerated carriers and enhance photocatalytic performance. These findings suggest that 2D CdZnHTs are possible candidates as water-splitting photocatalysts.

中文翻译：

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用于光催化分解水的二维 CdS/ZnO II 型异质结构

基于混合密度泛函计算探索了由 CdS 单层 (SL) 和 ZnO SL 组成的二维 (2D) CdS/ZnO 异质结构 (CdZnHT) 的电子结构。负的界面形成能表明 CdZnHT 的形成是放热的。CdZnHT 的带隙有利于吸收可见光，良好的带边位置使其在热力学上可以自发产生氧和氢。由电荷转移引起的跨界面形成的电场将减少光生载流子复合并促进载流子迁移。特别是，CdZnHT 是一种 II 型异质结构。氧化发生在氧化锌层，产氢发生在硫化镉层，这也将促进光生载流子的有效分离和迁移，提高光催化性能。这些发现表明，二维 CdZnHTs 可能是水分解光催化剂的候选者。