Electrochemical Valorization of Gaseous Small Molecules with Diamond-Based Catalysts

The valorization of gaseous small molecules, such as CO2, O2, and N2, through electrochemical processes holds promise in the production of useful chemicals while also addressing environmental challenges. Diamond-based electrocatalysts (D-ECs) with sp3-hybridized carbon atoms have been demonstrated to be effective for electrochemical valorization of gaseous small molecules because of their inherent architecture, extensive potential window, and electrochemical stability. This review provides a comprehensive overview of the electrochemical transformation of these gaseous small molecules on D-ECs, focusing specifically on the origins of active sites and the associated catalytic mechanisms related to adsorption tendencies. The strategies for design and development of efficient D-ECs, including heteroatom doping, nanostructuring, hybrid systems, surface functionalization, and adjustment of the local microenvironment during electrolysis, are also discussed, along with device engineering and application based on these D-ECs. Furthermore, the key challenges and opportunities in this emerging field are explored.