Spontaneous solar water splitting with decoupling of light absorption and electrocatalysis using silicon back-buried junction

• DOI: 10.1038/s41467-020-17660-0
• Publication Date: 2020-08-06T10:03:29Z
• Authors: Hui-Chun Fu; Purushothaman Var...; Chun-Ho Lin; Jr-Hau He
• Keywords: Decoupling (probability)

Abstract Converting sunlight into a storable form of energy by spontaneous water splitting is great interest but the difficulty in simultaneous management optical, electrical, and catalytic properties has limited efficiency photoelectrochemical (PEC) devices. Herein, we implemented decoupling scheme light harvesting electrocatalysis employing back-buried junction (BBJ) PEC cell design, which enables >95% front side light-harvesting, whereas electrochemical reaction conjunction with carrier separation/transport/collection occurs on back cell. The resultant silicon BBJ-PEC half-cell produces current density 40.51 mA cm −2 for hydrogen evolution minimizing losses (as low as 6.11, 1.76, 1.67 , respectively). Monolithic fabrication also three cells to be connected series single module, enabling unassisted solar water-splitting solar-to-hydrogen conversion 15.62% generation rate 240 μg h −1 .