Cu nanowire bridged Bi nanosheet arrays for efficient electrochemical CO2 reduction toward formate

Abstract

Abstract Electrocatalytic reduction of CO2 can not only reduce its concentration in atmosphere but also produces useful fuels and value-added chemicals like CO, CH4, and HCOOH, which has been considered as a promising means to resolve both environmental and energy problems. Recent studies showed that bismuth (Bi) in aqueous solution can electrocatalytically reduce CO2 to formic acid. However, individual Bi when used as electrocatalyst still suffers from low efficiency of electrocatalytic CO2 reduction reaction (CO2RR) to formate. Considering that copper (Cu) has good conductivity and feature of empty half 4s level that can behave as an electron donor or acceptor, here we synthesized Cu nanowires (NWs) bridged Bi nanosheets (Cu NWs-Bi NSs) arrays grown on carbon cloth through facile electrochemical routes. The as-obtained electrocatalysts showed larger partial current density and better selectivity for CO2RR to fomate than pristine Bi NSs. The enhanced electrocatalytic activity and improved selectivity could be attributed to improved charge transfer and electronic effect incurred by Cu NWs. The present work provides a new strategy for designing nanostructured electrocatalysts for highly efficient CO2RR.