The development of a polymer electrolyte with robust mechanical strength and exceptional electrochemical stability is crucial for alkaline water electrolysis while ensuring high hydroxide ion conductivity in low concentrations of KOH solution. The Ion-solvating Membrane Water Electrolysis (ISMWE) is gaining interest due to its adaptability to lower KOH solution concentrations, utilizing a polymer-based separator doped with KOH, resulting in a unified system consisting of polymer, water, and KOH, facilitating the use of non-platinum metal catalysts. Herin, we have employed the in-situ directing casting method to fabricate poly(2,5-benzimidazole) (ABPBI). The repeating benzimidazole units comprising the ABPBI membrane can retain significant amounts of KOH, leading to a dramatic increase in ion conductivity during electrolysis. The membrane was subjected to electrochemical evaluation through various conditions using an alkaline water electrolysis cell station, involving two different temperatures for cell operation, 60 ℃ and 70 ℃, and four different concentrations of KOH: 0.5M, 1M, 2M and 3M, utilizing both PGM catalysts and non-PGM catalysts. Additionally, we have fabricated ABPBI derivatives that exceed the mechanical and electrochemical performance of the pristine membrane. The physical characteristics of membranes are evaluated using techniques such as UTM, TGA, SEM, XRD, and XPS. From our results, the use of ABPBI polymer as Ion-solvating membrane, which allows for the utilization of high-efficiency and durable alkaline electrolysis. This study highlights the potential of ABPBI structures as the backbone and anion exchange sites for ISMWE operating with low KOH concentration solution. Figure 1
Read full abstract7-days of FREE Audio papers, translation & more with Prime
7-days of FREE Prime access