Work

Morphology controlled synthesis of 2-D Ni–Ni3S2 and Ni3S2 nanostructures on Ni foam towards oxygen evolution reaction

Year: 2017

Type: article

Abstract: Catalysts for oxygen evolution reactions (OER) are at the heart of key renewable energy technologies, and development of non-precious metal catalysts with high activity and stability remain a great challenge in this field. Among various material candidates, metal sulfides are receiving increasing attention. While morphology-dependent catalytic performances are well established in noble metal-based catalysts, relatively little is known for the morphology‒catalytic performance relationship in metal sulfide catalysts. In this study, uniform spider web-like Ni nanosheets–Ni 3 S 2 and honeycomb-like Ni 3 S 2 structures are deposited on nickel foam (Ni 3 S 2 /NF) by a facile one-step hydrothermal synthetic route. When used as an oxygen evolution electrode, the spider web-like Ni–Ni 3 S 2 /NF with the large exposed surface area shown excellent catalytic activity and stability with an overpotential of ~310 mV to achieve at 10 mA/cm 2 and a Tafel slope of 63 mV/dec in alkaline media, which is superior to the honeycomb-like structure without Ni nanosheet. The low Tafel slope of the spider web-like Ni–Ni 3 S 2 /NF represents one of the best OER kinetics among nickel sulfide-based OER catalysts. The results point to the fact that performance of the metal sulfide electrocatalysts might be fine-tuned and optimized with morphological controls.

Source: Nano Convergence

DOI: 10.1186/s40580-017-0101-6