Self-growing Cu/Sn bimetallic electrocatalysts on nitrogen-doped porous carbon cloth with 3D-hierarchical honeycomb structure for highly active carbon dioxide reduction

Abstract

The electrochemical CO2 reduction reaction (CO2RR) into liquid fuels is a promising avenue to both store intermittent renewable energy and reduce global CO2 emission, but daunting bottlenecks owing to poor selectivity, low activity and stability of the electrocatalysts. Herein, we report that bimetallic copper and tin are simultaneously deposited on the nitrogen doped porous carbon cloth (N-CC) via an efficient and facile co-electroplating strategy. The highly conductive N-doped porous carbon cloth as substrate enables a largely uniform distribution of N-doped defects, which can provide more active sites for the nucleation and growth of anchoring nano-sized Cn/Sn (3.39 nm). The as-prepared electrode (Cu(1)Sn(4)-N-CC), with a 3D-hierarchical porous honeycomb structure, could not only favor the diffusion of electrolyte and serve as “transfer posts” to confine the intermediates of reduced CO2, but also provide abundant terrace, ledge and kink atoms to function as active site for highly efficient CO2RR. As such, the obtained Cu(1)Sn(4)-N-CC electrode convert CO2 to formate with allured faradic efficiency (90.24 %), partial current density (15.56 mA cm−2) and production rate (173 μmol h-1 cm−2) at −0.97 VRHE, along with a long-term tolerance in CO2RR. This study may provide a new design for self-growing bimetallic catalyst on N-doped porous substrate to regulate advanced catalysts/electrodes for different applications.