SBIR Phase I:Improving Anion Exchange Membrane Water Electrolyzers via Novel Electrode Geometry

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) project is to enable very highly-efficient low-cost green hydrogen production by improving a key functional component of a promising water electrolysis technology. Green hydrogen is a chemical fuel and a feedstock with no associated CO2 emissions. In an effort to decarbonize our economy, green hydrogen can address sectors of our economy that are not easily electrified using clean electricity, for example steelmaking, chemicals, heating, and heavy transport such as shipping and aviation. However, the cost of green hydrogen is still too high to prompt large-scale adoption. The pure-water electrolyzers developed in this project can significantly reduce green hydrogen production costs compared to the current state-of-the-art: they require only water and electricity as inputs, and are entirely made of low-cost, non-toxic materials, utilizing domestic supply chains. They are modular, enabling the development of both large hydrogen production facilities and small decentralized systems, e.g., for on-site operations or refueling stations. This project will not only help the adoption of green hydrogen, it will also elucidate how the chemical and electrochemical modifications of active surfaces can more broadly be used to make electrochemical reactions, such as water splitting, more efficient.This SBIR Phase I project proposes to drastically improve a key component of an anion exchange membrane water electrolyzer (AEMEL): the anode electrode. The anode is the site of the oxygen evolution reaction (OER), a required but inefficient step during electrolytic hydrogen production. Enhancement of the OER kinetics by improved anode design, if translated to commercial AEMEL systems, would directly lead to a lower cost of green hydrogen. This project aims to replace the conventional two-layer anode, in which a complex catalyst layer is coated on top of a porous transport layer (PTL), with a simpler “unified” anode, in which the PTL is functionalized such that the catalyst layer is no longer necessary and the reaction kinetics are improved. In this project, two approaches to functionalize the PTL surface will be combined: the increase of the electrochemically active surface area (via etching, dealloying, and deposition techniques) and the increase of the intrinsic catalytic OER activity (via alloying and deposition techniques). This effort is expected to result in significantly improved AEMEL performance and lifetime, which will be evaluated using electrochemical methods, both ex situ (3-electrode cell) and in situ (in an operating electrolyzer).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.