Molecules, Vol. 29, Pages 1805: Hierarchically Structured Graphene Aerogel Supported Nickel & ndash;Cobalt Oxide Nanowires as an Efficient Electrocatalyst for Oxygen Evolution Reaction

Molecules, Vol. 29, Pages 1805: Hierarchically Structured Graphene Aerogel Supported Nickel–Cobalt Oxide Nanowires as an Efficient Electrocatalyst for Oxygen Evolution Reaction Molecules doi: 10.3390/molecules29081805 Authors: Donglei Guo Jiaqi Xu Guilong Liu Xu Yu The rational design of a heterostructure electrocatalyst is an attractive strategy to produce hydrogen energy by electrochemical water splitting. Herein, we have constructed hierarchically structured architectures by immobilizing nickel–cobalt oxide nanowires on/beneath the surface of reduced graphene aerogels (NiCoO2/rGAs) through solvent–thermal and activation treatments. The morphological structure of NiCoO2/rGAs was characterized by microscopic analysis, and the porous structure not only accelerates the electrolyte ion diffusion but also prevents the agglomeration of NiCoO2 nanowires, which is favorable to expose the large surface area and active sites. As further confirmed by the spectroscopic analysis, the tuned surface chemical state can boost the catalytic active sites to show the improved oxygen evolution reaction performance in alkaline electrolytes. Due to the synergistic effect of morphology and composition effect, NiCoO2/rGAs show the overpotential of 258 mV at the current density of 10 mA cm−2. Meanwhile, the small values of the Tafel slope and charge transfer resistance imply that NiCoO2/rGAs own fast kinetic behavior during the OER te...
Source: Molecules - Category: Chemistry Authors: Tags: Article Source Type: research