▎ 摘　　要

To improve the efficiency of electrochemical processes for environmental remediation, we present a new type of hybrid nanomaterials based on leaf-like copper-based quaternary transition metals and spongy monolayer graphene. To demonstrate the functionality of the hybrid electrocatalyst, fast and competent electrooxidation of water and glucose is shown. The mechanism of improved catalysis is ascribed to the synergetic catalytic effect of quaternary Cu-Ni-Fe-Co alloy with dendritic morphology along with the highly conductive and spongy structure of the graphene monolayer. It is shown that water oxidation can be performed at a low overpotential of 315 mV to reach a current denisty of 100 mA cm(-2) and a low Tafel slope of 63.06 mV dec(-1). Fast and sensitive amperometric detection of glucose at low concentrations (>= 1.3 mu M; 4153 mu A mM(-1) cm(-2)) in alkaline solutions is also presented. The compelling performance of the hybrid catalyst as compared with many noble-metal and non-precious metal electrocatalysts for water oxidation and electrochemical sensing is reported. (C) 2021 Elsevier Ltd. All rights reserved.