Dayan, Asridin Lee, DongHyun Azizi, Kobra Cleemann, Lars Nilausen Cho, Won­Chul Henkensmeier, Dirk 2025-04-08T09:00:37Z 2025-04-08T09:00:37Z 2025-04-07 2025-07 1614-6832 https://pubs.kist.re.kr/handle/201004/152184 A sulfonated para-polybenzimidazole (MS-PBI) membrane is thermally cured at 350 °C for 120 minutes. The thus obtained cMS-PBI membrane is insoluble in hot phosphoric acid solution (<5% soluble fraction), and is free of the known breaking points under alkaline conditions, i.e., no aromatic ether bonds, no quaternary ammonium groups, no N-alkylated neutral or positively charged imidazole groups. Indeed, a 6 months long alkaline stability test in 2 M KOH at 80 °C shows that cMS-PBI retains its dimensions and its weight without any sign of degradation. The room temperature conductivity increases within the first 24 days, and then remains constant at 192 ± 10 mS cm？1. At 80 °C, the conductivity in 3 M KOH reaches 682 mS cm？1. At 80 °C and with 2 M KOH feed solution, an electrolyzer using robust nickel foam electrodes has a performance of 0.975 A cm？2 at 2 V. With NiFe/Raney nickel, 3.52 A cm？2 (extrapolated) at 2 V are reached. Voltage remained stable in a 200 hours test. In conclusion, it is expected that ion solvating membranes like cMS-PBI can substitute anion exchange membranes in water electrolyzers, and by this improve their lifetime and reduce the cost of green hydrogen. English Wiley-VCH Verlag Thermally Cured Sulfonated para-PBI as Ion Solvating Membrane for Use in Water Electrolysis Article 10.1002/aenm.202500498 1 Advanced Energy Materials, v.15, no.25 Advanced Energy Materials 15 25 N scie scopus 001521306900024 Chemistry, Physical Energy & Fuels Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Energy & Fuels Materials Science Physics Article alkaline stability ion solvating membranes sulfonated para-PBI thermal curing water electrolysis