Structure Engineering of Transition-Metal-Based Catalysts toward Efficient Ethylene Glycol Oxidation: From Active Site Design to Techno-economic Analysis

Electrochemical ethylene glycol oxidation reaction (EGOR) provides a feasible solution for upgrading the polyethylene-terephthalate-based plastics into value-added chemicals/fuels, where its scaled implementation relies greatly on the development of high active and selective electrocatalysts. Recently, transition-metal-based materials (TMs) have emerged as promising candidates as efficient EGOR catalysts due to their earth abundance, low costs, and tunable electronic properties, while the effective construction of active structures is pivotal for selectively attaining desirable EGOR products. Here, a comprehensive review in the field is presented by summarizing the recent advances in TMs for electrochemical EG valorization, focusing on the design of active structures (e.g., geometric structure modulation, electronic property regulation, and reconstruction of cystaline interfaces) that afford a selective EGOR pathway. The reaction mechanisms and parameters in catalytic performance evaluation are particularly emphasized. In addition, the integrated systems combining the anodic EGOR process with other cathodic energy-conversion reactions (such as hydrogen evolving) have been reviewed, where economic feasibility of those EGOR-coupled electrolysis was discussed thoroughly. Finally, major challenges and opportunities for electrochemical EG conversion and future research directions are proposed.