High-Performance and Durable Membrane Electrode Assemblies Fabricated By Reactive Spray Deposition Technology for Proton Exchange Membrane Electrolyzers

Abstract

Water electrolysis is a very old and promising technology for hydrogen production that started about two centuries ago. Hydrogen, considered the best source for fuel and energy storage, can be produced by the electrochemical conversion of water into hydrogen and oxygen through the water electrolysis process. Since the 1950s, proton exchange membrane water electrolyzers (PEMWEs) have been commercially developed as a green source of high-purity hydrogen for many chemical applications as well as energy storage. However, high cost, high maintenance, low durability, poor safety, poor reliability, and low efficiency of PEMWEs compared to other available technologies have hampered their widespread commercialization. To address the economic and technical issues of the PEMWEs, research should consider improved electrocatalysts, low cost electrodes, corrosive resistant electrodes, reduction of electrode surface tension, and lower membrane resistance and hydrogen crossover [1, 2].This work presents high-performance, cost-effective and durable membrane electrode assemblies (MEAs; 86 cm2 active area) developed by the unique reactive spray deposition technology (RSDT) [3-6]. The RSDT-fabricated MEAs possess total platinum group metal (PGM) loading of 0.2-0.3 mgPt cm-2 for the Pt/C cathode catalyst layer, and 0.2-0.3 mgIr cm-2 for the Ir/IrOx anode catalyst layer, respectively. This is an order of magnitude reduction of the PGM loadings in the catalyst layers in comparison to the state-of-the-art commercial MEAs, resulting in substantial reduction of the cost of PEMWEs. An ultra-thin Pt recombination layer (Pt RL), positioned between two PEM membranes, was fabricated by RSDT to lower hydrogen cross-over and eliminate the PEMWE’s safety concerns. Furthermore, the RSDT-fabricated MEAs showed stable performance for 3000 hours operation at 1.8 A cm-2, 50°C, 400 psi hydrogen pressure and ambient oxygen pressure without significant loss in the polarization performance.