Hydrogen production by membrane water splitting technologies is a sustainable method to synthesize hydrogen and provides an alternative to hydrogen production instead of conventional process of synthesizing hydrogen from steam methane reforming. A hybrid polymer electrolyte membrane electrolyzer operational at working temperature of above 80–200°C is advantageous for faster electrochemical kinetics, higher current exchange density, and more resistance to fuel impurities. Phosphoric acid (PA) doping onto polybenzimidazole (PBI) membrane shows significant improvement in proton conductivities, permeability, and thermal stability. PBI-based electrolyzer is relatively new to the hydrogen production technologies as compared to Nafion-based electrolyzer. However, the high cost of purchasing Nafion membrane and inability to execute electrolysis operational above 90°C has sparked new interest on PBI-based membrane, which is known for its good thermal stability.
Part of the book: Advances In Hydrogen Generation Technologies