Gallium nitride nanowire as a linker of molybdenum sulfides and silicon for photoelectrocatalytic water splitting

• Published in: Nature communications Vol. 9; no. 1; pp. 3856 - 8
• Main Authors: Zhou, Baowen, Kong, Xianghua, Vanka, Srinivas, Chu, Sheng, Ghamari, Pegah, Wang, Yichen, Pant, Nick, Shih, Ishiang, Guo, Hong, Mi, Zetian
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 21.09.2018; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/146; 147/135; 147/143; 639/301/299/890; 639/301/357/1016; 639/4077/909/4101/4102; 639/638/439/943; Catalysts; Charge efficiency; Current carriers; Electrodes; Electronics; Electronics industry; ENGINEERING; Gallium; Gallium nitrides; Heavy metals; Heterostructures; Humanities and Social Sciences; Hydrogen-based energy; Migration; Molybdenum; Molybdenum sulfides; multidisciplinary; Nanotechnology; Nanowires; Noble metals; Science; Science (multidisciplinary); Silicon; Solar energy; Solar energy conversion; Sulfides; Water splitting
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-06140-1

The combination of earth-abundant catalysts and semiconductors, for example, molybdenum sulfides and planar silicon, presents a promising avenue for the large-scale conversion of solar energy to hydrogen. The inferior interface between molybdenum sulfides and planar silicon, however, severely suppresses charge carrier extraction, thus limiting the performance. Here, we demonstrate that defect-free gallium nitride nanowire is ideally used as a linker of planar silicon and molybdenum sulfides to produce a high-quality shell-core heterostructure. Theoretical calculations revealed that the unique electronic interaction and the excellent geometric-matching structure between gallium nitride and molybdenum sulfides enabled an ideal electron-migration channel for high charge carrier extraction efficiency, leading to outstanding performance. A benchmarking current density of 40 ± 1 mA cm −2 at 0 V vs. reversible hydrogen electrode, the highest value ever reported for a planar silicon electrode without noble metals, and a large onset potential of +0.4 V were achieved under standard one-sun illumination. Sunlight-harvesting materials require the clean integration of light-absorbing and catalytic components to be efficient. Here, authors link silicon photoelectrodes and molybdenum sulfide catalysts with defect-free gallium nitride nanowire to improve photoelectrochemical hydrogen evolution.