NMR methods for studying electrocatalysis.

The combination of electrochemical measurements with spectroscopic characterizations provides valuable insights into reaction mechanisms. Nuclear magnetic resonance (NMR) spectroscopy, as a powerful technique due to its atomic specificity and versatility in studying gas, liquid, and solid, allows the study of electrolyte solution, catalyst and catalyst-adsorbate interfaces. When applied in , NMR can offer molecular-level insights into various electrochemical processes. NMR has been applied extensively in battery research, but relatively underexplored for electrocatalysis in the past two decades. In this mini review, we first introduce the electrochemical NMR setups, categorized by different probe designs. Then we review the applications of NMR for monitoring the electrolyte solution and the catalyst-adsorbate interface. Considering the high environmental impact of electrochemical conversion of CO into value-added products, we zoom in to the use of NMR in studying electrochemical CO reduction. Finally, we provide our perspective on further developing and applying NMR methods for understanding the complex reaction network of Cu-catalyzed electrochemical CO reduction.