Amorphous urchin-like copper@nanosilica hybrid for efficient CO2 electroreduction to C2+products

Currently most of research efforts for selective electrocatalysis CO2 reduction to C2+ products have relied on crystalline Cu-based catalysts; amorphous Cu with abundant low-coordinated atoms holds greater promise for this conversion yet remains relatively underexplored. Here we report an amorphous urchin-like Cu@nanosilica hybrid synthesized by electrostatic coupling Si polyanions with Cu salt in hydrothermal processes. The Cu@nanosilica electrocatalyst displays excellent CO2 electroreduction activity and selectivity with a Faradic efficiency of 70.5% for C2+ product production, and higher stability compared to the crystalline Cu counterpart. The solar-driven CO2 electrolysis yields an energy efficiency of 20% for C2+ product production. Mechanism study reveals that the urchin-like Cu@nanosilica catalyst with amorphous Cu/Cu+ dispersion enhances CO2 adsorption and activation to facilitate generation of CO2* and possible CO* intermediates, and suppresses hydrogen evolution concurrently. The combined effects of both aspects promote efficient C2+ product production from CO2 electroreduction. (C) 2021 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

The study introduces an amorphous urchin-like Cu@nanosilica hybrid as an efficient electrocatalyst for CO2 reduction with high Faradic efficiency and stability. Mechanistic study reveals that the amorphous Cu/Cu+ dispersion in the catalyst enhances CO2 adsorption and activation, promoting efficient production of C2+ products while suppressing hydrogen evolution.