Advancements in electrochemical methanol synthesis from CO2: Mechanisms and catalyst developments

Abstract

Electrochemical CO2 reduction (eCO2R) has emerged as a promising avenue, offering the dual benefits of mitigating atmospheric CO2 while generating value-added chemicals and fuels. In particular, eCO2R to methanol (CH3OH) holds significant promise due to its various applications in energy and chemical industries, yet only a few studies have been reported thus far, primarily due to the complexity of its reaction pathway. This review first focuses on elucidating the intricate reaction mechanisms involved in CH3OH production via eCO2R. Then, we highlight recent advancements in catalyst designs, including Cu-based, non-Cu-based, and CoPc-based electrocatalysts. Finally, we summarize the in-situ analysis techniques, including vibrational spectroscopy, X-ray absorption spectroscopy, and differential electrochemical mass spectrometry, which help gain an in-depth understanding of the reaction intermediate, surface/electronic/geometric structures of electrocatalysts under the working environments. By providing a comprehensive overview of eCO2R pathways towards CH3OH and introducing rational design principles for electrocatalysts, we believe this review can significantly contribute to the advancement of efficient and selective CH3OH production and offer valuable insights into the field.