Wang Jiajun, Meng Jie, Li Qunxiang, Yang Jinlong
Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Materials Chemistry, Ministry of Education, College of Chemistry, Tianjin Normal University, Tianjin 300387, China.
Hefei National Laboratory for Physical Sciences at the Microscale & Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Phys Chem Chem Phys. 2016 Jun 22;18(25):17029-36. doi: 10.1039/c6cp01001f.
Recently, various single-layer materials have been explored as desirable photocatalyts for water splitting. In this work, based on extensive density functional theory calculations, we examine the geometric, electronic, optical, and potential photocatalytic properties of single-layer cadmium chalcogenides (CdX sheets, X = S, Se, and Te), which are cleaved from the (001) plane of the bulk wurtzite structure. The predicted formation energies have relatively low values and a suitable substrate (i.e. graphene) that can effectively stabilize CdX sheets, which imply that the fabrication and application of CdX sheets are highly possible in experiments. The calculated band gaps, band edge positions and optical absorptions clearly reveal that CdSe and CdTe sheets are promising photocatalysts for water splitting driven by visible light. Moreover, the band gaps and band edge positions of three CdX sheets can be effectively tuned by applying biaxial strain, which then can enhance their photocatalytic performance. These theoretical findings imply that CdX sheets are promising candidates for photocatalytic water splitting.
最近，人们探索了各种单层材料作为水分解的理想光催化剂。在这项工作中，基于广泛的密度泛函理论计算，我们研究了从块状纤锌矿结构的（001）平面解理得到的单层硫族镉化物（CdX 片，X = S、Se 和 Te）的几何、电子、光学和潜在光催化性能。预测的形成能具有相对较低的值，并且存在可以有效稳定 CdX 片的合适衬底（即石墨烯），这意味着 CdX 片在实验中具有很高的制备和应用可能性。计算得到的带隙、带边位置和光吸收清楚地表明，CdSe 和 CdTe 片是可见光驱动水分解的有前途的光催化剂。此外，通过施加双轴应变可以有效地调节三种 CdX 片的带隙和带边位置，进而可以提高它们的光催化性能。这些理论发现表明，CdX 片是光催化水分解的有前途的候选材料。
