A universal Strategy of Constructing Cr-NiFe MOF/CMC Aerogel Composite Catalysts for Efficient Oxygen Evolution Reaction

Abstract

Metal-organic frameworks (MOFs)-based aerogel composite display extensive applications in such as catalysis, chemical, separation and biology aspects due to their high specific surface area, tailored structure and component features. The combination of the MOFS structure from the brittle powder crystal state onto the flexible multilayer aerogel carrier can result in the exposure of a greater number of active sites, thereby greatly accelerate the mass transfer rate and enhance the catalytic activity. Herein, we proposes a universal low-temperature sol-gel method to synthesize the composite of NiFe MOF on carboxymethyl cellulose (CMC) aerogel. The proposed methodology is characterized by its gentleness, low cost, and universal applicability. Moreover, the catalytic activity of NiFe MOF was greatly enhanced by Cr doping. As a result, the 10% Cr-NiFe MOF/CMC aerogel composite exhibits a low oxygen precipitation overpotential of 235 mV and low Tafel slope of 53.7 mV·dec-1 at a current density of 10 mA·cm-2, as well as displays continuous cycling stability of more than 210 h. The present catalytic activity and good corrosion resistance are comparable with the reported noble metal catalysts and even superior to most reported Ni and/or Fe-based MOF catalysts. This work demonstrates the promising potential of MOFs/CMC aerogel composite in the development of highly effective electrocatalysts.