A Co(3)O(4)-CDots-C(3)N(4) three component electrocatalyst design concept for efficient and tunable CO(2) reduction to syngas

Syngas, a CO and H(2) mixture mostly generated from non-renewable fossil fuels, is an essential feedstock for production of liquid fuels. Electrochemical reduction of CO(2) and H(+)/H(2)O is an alternative renewable route to produce syngas. Here we introduce the concept of coupling a hydrogen evolution reaction (HER) catalyst with a CDots/C(3)N(4) composite (a CO(2) reduction catalyst) to achieve a cheap, stable, selective and efficient route for tunable syngas production. Co(3)O(4), MoS(2), Au and Pt serve as the HER component. The Co(3)O(4)-CDots-C(3)N(4) electrocatalyst is found to be the most efficient among the combinations studied. The H(2)/CO ratio of the produced syngas is tunable from 0.07:1 to 4:1 by controlling the potential. This catalyst is highly stable for syngas generation (over 100 h) with no other products besides CO and H(2). Insight into the mechanisms balancing between CO(2) reduction and H(2) evolution when applying the HER-CDots-C(3)N(4) catalyst concept is provided.