Electrochemical CO2-to-ethylene conversion on metal-free covalent quinazoline network-derived electrodes

摘要

Electrocatalytic CO2 reduction to produce multi-carbon (C_(2+)) chemicals represents a highly attractive route for CO2 utilization, particularly CO2-to-ethene conversion toward fuel generation from renewable resources. However, state-of-the-art electrocatalysts are mainly limited to Cu-derived electrodes. Herein, metal-free nanoporous and deflect-abundant covalent quinazoline network (CQN)-derived electrocatalysts displayed promising catalytic efficiency and selectivity in CO2-to-ethene conversion. The highest Faradaic efficiency of ethene production (FEC2H4) achieved 61.1 at 1.07 V (versus reversible hydrogen electrode RHE) by modified CQN-derived electrodes, surpassing the current metal-free systems in CO2-to-ethene conversion. Structural characterization and theoretical calculation underscored the critical role of deflect creation and the periphery nitrogen species in the tricycloquinazoline (TCQ) units in CO2 adsorption, hydro-genation, and subsequent C-C coupling reaction to afford ethene. The achievements made in this work provide an alternative platform of metal-free nanocatalysts toward CO2-to-C_(2+) products via electrore-duction by leveraging the highly porous, extensively conjugated, and aza-fused ring-abundant two-dimensional networks.