Influence of Bubbles on the Energy Conversion Efficiency of Electrochemical Reactors

Bubbles are known to influence energy and mass transfer in gas-evolving electrodes. However, we lack a detailed understanding on the intricate dependencies between bubble evolution processes and electrochemical phenomena. This review discusses our current knowledge on the effects of bubbles on electrochemical systems with the aim to identify opportunities and motivate future research in this area. We first provide a base background on the physics of bubble evolution as it relates to electrochemical processes. Then we outline how bubbles affect energy efficiency of electrode processes, detailing the bubble-induced impacts on activation, ohmic, and concentration overpotentials. Lastly, we describe different strategies to mitigate losses and how to exploit bubbles to enhance electrochemical reactions.