Efficient strategies for the preparation of non-noble metal catalysts for electrocatalytic glycerol oxidation towards high-value-added chemicals

Glycerol is an important by-product of the biodiesel production process, is cheap and abundant, and can be converted into a variety of high-value-added fine chemicals. The glycerol electrooxidation reaction (GEOR) has significant application potential owing to its lack of oxidant requirements and the generation of clean hydrogen energy at the cathode. Currently, noble metal materials serve as effective catalysts for the GEOR, but their high cost and scarcity limit their commercial applications. Consequently, there is an urgent necessity to develop efficient non-noble metal catalysts for the GEOR to replace noble metal catalysts. This paper briefly introduces the reaction mechanism of the GEOR and reviews recent research progress on the synthesis of transition metal-based GEOR catalysts, focusing on Ni-, Co-, Cu-, and Mn-based catalysts. A particular emphasis is placed on the strategies to improve the GEOR performance of different non-noble metal catalysts, which include alloying, doping engineering, defect engineering, heterostructure construction, crystal phase regulation, morphology control and composite synthesis. Finally, we provide a comprehensive discussion on the challenges and future prospects of non-noble metal catalysts in the GEOR.