PHOTOELECTROCHEMISTRY



Porous Ni–O/Ni/Si photoanode



Chem. Commun., 2019, doi:10.1039/C8CC08146H



Photoelectrochemical (PEC) water splitting is an attractive strategy to convert solar energy into chemical fuels with zero-carbon. However, the photoanode, related to the oxygen evolution reaction (OER), is still regarded as a bottleneck due to the relatively complex 4-electron reaction mechanism. Si has been studied as a good photoanode material, and Ni oxides (Ni–O) is effective catalyst for OER in basic solution. However, the reported methods to integrate the Ni–O on Si, such as evaporation and sputtering, can hardly produce porous surface which can be very important to improve their catalytic effect. Through converting the electrodeposited porous Ni–S by activation in basic solution, the research reported by Huanget al. exhibits an unusual but simple way to obtain porous Ni–O catalyst on Ni-protected Si photoanode, leading to the superior PEC activity. An energy conversion efficiency of 3.2% under 1 sun illumination, and a high stability of 100 h continuous PEC testing were achieved. Furthermore, through clarifying the contribution of non-faradaic process, etc, the oxidation of Ni²⁺ to Ni³⁺, on the PEC current–potential(J–V) curves, this study provides a criterion for separating the oxidation effect from the J–V curve, ensuring the true PEC activity.



Dawei Cao (Jiangsu University, Zhenjiang, China)



doi: 10.1088/1674-4926/40/1/010202