Economical Production of Hydrogen Through Development of Novel, High Efficiency Electrocatalysts for Alkaline Membrane Electrolysis

Efficient, cost effective production of hydrogen from non-carbon based sources is a key barrier to widespread implementation of fuel cells for transportation and stationary power. Ion exchange membrane-based electrolysis is a promising technology for clean generation of pure hydrogen, but significant advances are required in order to provide cost-competitive hydrogen source for energy markets. Commercial membrane-based electrolyzers are based on proton exchange membranes (PEM), which require highly expensive catalyst and flow field materials such as noble metals and titanium due to the acidic environment of the membrane. In addition, the operating currents typically utilized in PEM systems to counteract the high material costs result in less than ideal efficiency, even though the membrane systems are inherently more efficient than liquid systems. The project proposed here addresses both of these issues by replacing the proton exchange membrane with an anion exchange membrane (AEM) and exploring new pyrochlore-based catalysts. Moving to a basic environment also enables the flow fields to made from less expensive materials. In addition, the classes of catalyst materials which are stable in the alkaline membrane environment are expanded vs. the acid environment, enabling higher overall hydrogen generation efficiency. Phase 1 will focus on the synthesis of 4 different catalyst types within the pyrochlore class. While the key focus of this project is the catalyst, initial work on alternate membranes will be performed to enable even higher reaction efficiency through development of more conductive membranes. Promising materials will be incorporated into processing studies to optimize electrode fabrication technique, and will be tested in commercial electrolyzer hardware. In Phase 2, additional characterization will be performed to assess the relation between composition, processing-induced-morphology, and resultant properties in conditions relevant to electrolyzer operation. Scale up will also occur to fabricate a full-sized commercial cell stack. Commercial Applications and Other Benefits: This research and development effort is designed to transform hydrogen-based energy storage into an enabling technology for the reduction of fossil fuel use by overcoming the present economic constraints preventing its widespread application. Protons electrolyzers already serve a wide variety of applications, including metals processing, chemical manufacturing, electronics manufacturing, hydrogenation, electrical generator cooling, fiber optic cable manufacturing, and argon purification. Next generation products currently under development include higher pressure systems for the fueling and energy storage markets as well as regenerative fuel cells for telecommunications backup power systems. All of these technologies are on pathways to commercialization and utilize various Government and internal sources of funding to advance their state of technical readiness. Protons mission is clearly to move advanced technology PEM products into hydrogen energy applications as those markets emerge in the coming years.