Steering CO2 electroreduction toward methane or ethylene production

Abstract

Highly selective production of valuable hydrocarbons from CO 2 electroreduction is particularly desirable yet challenging. Herein we steer CO 2 electroreduction toward methane (CH 4 ) or ethylene (C 2 H 4 ) production with high selectivity by controlling the loading of copper phosphate (Cu 3 (PO 4 ) 2 ) nanosheets on electrode. The low loading (0.28 mg cm -2 ) and high loading (2.24 mg cm -2 ) of Cu 3 (PO 4 ) 2 nanosheets lead to Faradaic efficiency of 76% for CH 4 and 67% for C 2 H 4 , respectively. Mechanism investigation reveals that metallic Cu nanoparticles are derived during electrolysis at low Cu 3 (PO 4 ) 2 loading condition, favoring *CO hydrogenation to CH 4 production. At high Cu 3 (PO 4 ) 2 loading condition, the metallic Cu nanoparticles decorated with Cu 3 (PO 4 ) 2 are produced, which can stabilize and promote the dimerization of *CO to C 2 H 4 formation. This work provides new insights into controlling the electrocatalytic CO 2 reduction from C 1 to C 2 products by designing derivatives of Cu-based catalyst. Herein we demonstrate the controlled production of CH 4 or C 2 H 4 from electrocatalytic CO 2 reduction by changing the loading amount of Cu 3 (PO 4 ) 2 nanosheets on electrode. The maximum CH 4 and C 2 H 4 Faradaic efficiency (FE) can reach 76% and 67% at Cu 3 (PO 4 ) 2 loading of 0.28 mg cm -2 (×8) and 2.24 mg cm -2 (×64), respectively. • CO 2 electroreduction to CH 4 or C 2 H 4 can be easily tuned by regulating the loading amount of Cu 3 (PO 4 ) 2 on electrode. • The highest Faradaic efficiency of CO 2 electroreduction for CH 4 and C 2 H 4 can reach to 76% and 67%, respectively. • The metallic Cu nanoparticles decorated with Cu 3 (PO 4 ) 2 can promote the dimerization of *CO to C 2 H 4 formation.