文献类型：期刊文献

英文题名：High solar-to-hydrogen efficiency S-scheme SnC/g-C6N6 van der Waals heterojunction for solar water splitting

作者：Sheng, Zhuyuan[1];Sun, Zhengdong[1];Zhu, Junhao[1];Ma, Jiaxin[1];Huang, YingYing[1];Zhang, Meng[1]

机构：[1]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China

年份：2026

卷号：245

外文期刊名：INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

收录：;EI(收录号：20262320829211);WOS:【SCI-EXPANDED(收录号:WOS:001785414800001)】；

基金：Acknowledgements The work is financially supported by East China University of Science and Technology, China. In addition, we would like to express our sincere appreciation to our esteemed collaborators and dedicated team members for their invaluable contributions to this work. It is through their collective efforts that we are able to advance scientific understanding and drive innovation in our field.

语种：英文

外文关键词：S -scheme heterojunction; Photocatalytic water splitting; Solar-to-hydrogen efficiency; Density functional theory calculation

摘要：First-principles calculations demonstrate that the SnC/g-C6N6 van der Waals heterojunction is structurally stable and exhibits excellent photocatalytic performance for solar water splitting. The solar-to-hydrogen (STH) efficiency is estimated to be 82.12% in the unstrained system and increases to 84.84% under biaxial strain, representing an ideal upper limit. A more realistic PySTH efficiency of 17.94% indicates strong yet achievable photocatalytic potential. This high efficiency originates from a built-in electric field (8.56 eV potential difference) that drives an S-scheme charge-transfer mechanism, enabling efficient electron-hole separation. Heterojunction formation converts SnC into a direct bandgap semiconductor and improves band-edge alignment, enhancing visible-light absorption by nearly six times compared with isolated monolayers. The oxygen evolution reaction is thermodynamically favorable, while the hydrogen evolution reaction requires a low overpotential of 0.62 eV, reduced to 0.09 eV under tensile strain. These results identify SnC/g-C6N6 as a stable and efficient strain-tunable S-scheme photocatalyst for solar water splitting.