Assembly of a Highly Efficient Molecular Device with (CNCbl)‐MWCNT/CP as Electrode for CO2 Reduction Coupled to Water Oxidation

Abstract In this work, a novel molecular device was assembled with cyanocobalamin (CNCbl)‐MWCNT/CP as an electrode for CO 2 reduction coupled to water oxidation. In the half cell of water oxidation, the electrode displayed a stable current density of more than 10 h, showing excellent electrocatalytic stability of CNCbl‐MWCNT/CP. For only CO 2 reduction, the electrode displayed a turnover number (TON CO ) and turnover frequency (TOF CO ) of 295390 and 8.2 s −1 , respectively, and excellent Faradaic efficiency (FE CO ) of 96 % at −1.0 V vs. RHE. When using (CNCbl)‐MWCNT/CP as a bifunctional electrode in a full‐cell system for 3 h at 2.7 V, the gas products were 63.89 μmol of CO, 2.42 μmol of H 2, and 26.93 μmol of O 2 , showing a high FE CO of ca. 92 %. The unique structural advantages of CNCbl could improve electrocatalytic CO 2 reduction and water oxidation.