(482e) Design and Engineering of Membraneless Electrolysis Devices

Although the sun is a promising energy source to renewably meet society’s demands, the storage of solar energy during intermittent hours remains a significant challenge. One possible solution is to electrolyze water into storable fuels, but the present capital costs are still too high for this to be viable. The current state of the art technology relies on the use of ion selective membranes, which are expensive and prone to degradation and failure. The extreme sensitivity of membranes to impurities can incur significant costs associated with installation, maintenance, and electrolyte purification. Our group has focused on creating low cost devices by designing electrolyzers which can operate safely without a membrane. In particular, we have investigated devices based on mesh flow-through electrodes. In these studies, we were able to demonstrate safe and reliable separation of H₂ and O₂ product gasses using forced convection.[1] By selectively depositing the electrocatalyst on only one side of the mesh substrate, we were even able to separate the product gasses with high purity in an un-pumped, free-standing electrolyte.[2] In this talk, we discuss the present challenges for membraneless electrolysis as well as the opportunities going forward.

[1] O’Neil G D, et al. 2016 Hydrogen Production with a Simple and Scalable Membraneless Electrolyzer J. Electrochem. Soc. 163 F3012–9

[2] Davis, et al. 2017 Floating Membraneless PV-Electrolyzer Based on Buoyancy-Driven Product Separation Manuscript in Submission.