Controlled-potential electrolysis for evaluating molecular electrocatalysts

As global energy demands continue to increase, the urgency with which we need to end our reliance on fossil fuel resources has prompted significant interest in the development of molecular electrocatalysts to mediate the electrochemical reactions relevant to renewable energy storage and energy usage. Voltammetric methods, especially cyclic voltammetry, and bulk electrolysis are powerful electrochemical techniques that can provide quantitative metrics for benchmarking the activity of such molecular systems under electrocatalytic conditions. In particular, by using controlled-potential electrolysis, the selectivity, efficiency, and stability of an electrocatalyst can be probed. In this review, we provide an introduction to this technique to assist researchers in their study of molecular electrocatalysts in the context of renewable energy. Fundamental aspects of the experimental setup, practical considerations, and best-practice recommendations are discussed. Several case studies are then presented to highlight this electrochemical method in action for the analysis of molecular electrocatalysts pertinent to energy-related applications.