Electrooxidation of 5-Hydroxymethylfurfural and Electroreduction of Nitrobenzene by Hollow CoFeP Cubes/rGO/Ni Foam

Abstract

Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylate (FDCA) has attracted great attentions due to being capable of producing degradable plastics. But, HMF electrooxidation still faces challenges such as high overpotentials and sluggish kinetics. In the meanwhile, H2 evolution in the cathode is less cost-effective than the reactions producing valuable chemicals. In view of this, MOF-derived CoFeP cube anchored on rGO-encapsulated nickel foam (NF) via a facile wet-chemical method is reported. The CoFeP-rGO delivers a low potential of 1.38 V at 100 mA cm-2 of current density in 1M KOH and 10 mM HMF with 100% conversion and a yield of 96% of FDCA and 100% Faraday efficiency (FE). It acts as a bifunctional catalyst, demonstrating electrocatalytic reduction of nitrobenzene (NB) at low overpotential with 91% of the conversion. In the proposed mechanism, the CoFeP-rGO interface is proved to play a crucial role in increasing the catalytic activities via promoting dispersion of the CoFeP nanocrystals on the substrate and accelerate electron transfer rate across the interface.