“…[1][2][3] To solve these problems, it is especially urgent and important to convert CO 2 to value-added fuels or chemicals via different CO 2 fixation technologies. [4][5][6] Using photosynthesis as an example, 7,8 it has been proposed to engage in artificial photosynthesis by using a combination electrochemical CO 2 reduction and water splitting coupled electrocatalytic system. In a typical overall coupled electrocatalytic reaction of CO 2 + H 2 O, the anode participates in the half reaction of water splitting into the oxygen evolution reaction (OER), and at the cathode, the carbon dioxide reduction reaction (CO 2 RR) occurs to produce fuels such as CO, CH 3 OH, HCOOH, CH 4 , and other high energy/density chemical fuels (CFs), [9][10][11][12] which can be expressed as an overall reaction of CO 2 + H 2 O → CF + O 2 .…”