Ultrafine Cu nanoclusters confined within covalent organic frameworks for efficient electroreduction of CO_(2) to CH_(4) by synergistic strategy

Electrocatalytic CO_(2) reduction(ECR)to high value-added chemicals by using renewable electricity presents a promising strategy to realize“carbon neutrality”.However,the ECR system is still limited by its low current density and poor CO_(2) utilization efficiency.Herein,by using the confinement effect of covalent organic frame-works(COFs)to confine the in-situ growth of metal nanoclusters(NCs),we develop a series of Cu NCs encap-sulated on COF catalysts(Cu-NC@COF)for ECR.Among them,Cu-NC@CuPc-COF as a gas diffusion electrode(GDE)achieves a maximum CO_(2)-to-CH_(4) Faradaic efficiency of 74±3%(at-1.0 V vs.Reversible Hydrogen Electrode(RHE))with a current density of 538±31 mA cm^(-2)(at-1.2 V vs.RHE)in a flow cell,making it one of the best among reported materials.More importantly,the current density is much higher than the relevant industrial current density(200 mA cm^(-2)),indicating the potential for industrial application.This work opens up new possibilities for the design of ECR catalysts that utilize synergistic strategy.