(400a) High Speed Imaging of Bubble Flows in Membraneless Electrochemical Cells

Membraneless cells have been proposed as a low cost reactor design for water electrolysis. In order to safely and efficiently separate the product gases, however, many of these membraneless designs require flowing electrolyte. While it is generally recognized that the dynamics of multiphase flow can strongly impact cell performance, attempts to characterize gas evolving electrodes can be non-trivial due to the complexity of the underlying physics. In this study, we use high speed video to capture the flow of bubbles in a membraneless electrolysis system. Post-processing analysis is able to detect the bubble size, location, and velocity during operation. This non-invasive technique can be used to quantify gas evolution efficiency yields, bubble size distributions, current distributions, and product gas cross-over. These techniques can be applied to monitor operating conditions as well as guide the design of future electrolysis systems.