Nickel sulfide nanocrystals for electrochemical and photoelectrochemical hydrogen generation

摘要: Photoelectrochemical water splitting has been considered as the most promising technology for generating hydrogen energy. Herein, we report nickel sulfide nanocrystals (NCs) excellent catalysts electrochemical and solar-driven photoelectrochemical (PEC) evolution. Two polymorphic NiS NiS1.97 NCs were synthesized with a controlled composition, showed higher electrocatalytic activity than toward hydrogen/oxygen evolution reactions in 0.5 M H2SO4 1 KOH. Photocathodes fabricated by growing directly onto Si nanowire (NW) arrays. The deposition of results PEC performance both acid alkaline electroytes; photocurrent is 10 mA cm−2 (at 0 V vs. RHE) onset potential 0.2 V. In contrast, Si-NiS1.97 photocathode exhibits much lower less stability. Detailed structure analysis using X-ray photoelectron spectroscopy reveals that more metallic retains same electronic structures during catalytic reaction. high should be main cause this enhanced performance, efficient water-splitting Si-based cells.