Electrochemical reduction of CO2 in a proton conducting solid oxide electrolyser

摘要

Synthetic hydrocarbon fuels from CO2/H2O are proposed as alternatives to hydrogen as an energy carrier to enable a carbon neutral energy cycle, given their inherent advantages of high H/C ratio and convenience of storage and transportation. Here we demonstrate the successful electrochemical reduction of CO2 into CO and CH4 in a proton conducting solid oxide electrolyser based on BaCe_(0.5)Zr_(0.3)Y_(0.16)Zn_(0.04)O_(3-δ) (BCZYZ) electrolyte and a composite iron/iron oxide cathode. The production of CH4 and CO reaches 0.07 and 3.25 ml min~(-1) cm~(-2), respectively, with 1.5 A cm~(-2) at 614 °C. The overall CO2 conversion rate in the electrochemical reduction process is 65%.