Poly(terphenyl-diphenylmethane piperidinium) anion exchange membranes assembled with non-precious metal electrodes for high-performance water electrolysis
Anion exchange membrane water electrolysis (AEMWE) offers cost and dynamic-response advantages over proton exchange membrane systems, yet commercial deployment is constrained by the alkaline stability of anion exchange membranes (AEMs) and the sluggish kinetics of non-precious metal catalysts. This work reports a series of poly(terphenyl-diphenylmethane piperidinium) (QPDPMTP) membranes synthesized with varied diphenylmethane (DPM) content. The alkyl chain of DPM induces pronounced microphase separation and elevates free volume fraction, yielding an OH− conductivity of 152 mS cm−1 at 80 °C for QPDPMTP-10. After 1032 h immersion in 6 M NaOH at 80 °C, the membrane retains 90.7% of its initial conductivity. An AEMWE cell integrating QPDPMTP-10 with a non-precious NiFeCo LDH/NiS/NF anode achieves 3.11 A cm−2 at 2 V in 1 M KOH at 80 °C and sustains 1 A cm−2 for 1800 h under gradient KOH concentration. These results establish a viable pathway for durable, low-cost AEMWE systems.