RESUMEN
Anion exchange membrane water electrolysis (AEMWE) for hydrogen production combines the advantages of proton exchange membrane water electrolysis and alkaline water electrolysis. Several strategies have been adopted to improve the performance of AEMWE and to obtain membranes with high hydroxide ion conductivity, low gas permeation, and high durability. In this work AEMs reinforced with poly[2,2'-(p-oxydiphenylene)-5,5'-benzimidazole] (PBIO) polymer fibres have been developed. A fibre web of PBIO prepared by electrospinning was impregnated into the poly(terphenylene) mTPN ionomer. The membranes are strengthened by the formation of a strong surface interaction between the reinforcement and the ionomer and by the expansion of the reinforcement over the membrane thickness. The hydroxide ion conductivity, thermal stability, dimensional swelling, mechanical properties, and hydrogen crossover of the reinforced membranes were compared with the characteristics of the non-reinforced counterpart. The incorporation of PBIO nanofibre reinforcement into the membrane reduced hydrogen crossover and improved tensile properties, without affecting hydroxide conductivity. PBIO-reinforced mTPN membrane was assessed in a PGM-free 5â cm2 AEMWE single cell using NiFe oxide anode and NiMo cathode catalysts, at a cell temperature of 50 °C and with 1â M KOH fed to the anode. The performance of the cell increased continuously over the 260â hours test period, reaching 2.06â V at 1.0â A cm-2.
RESUMEN
Mechanical and chemical stability of proton exchange membranes are crucial requirements for the development of fuel cells for durable energy conversion. To tackle this challenge, bi-functional nanoclays grafted with amino groups and with embedded radical scavengers, that is, CeO2 nanoparticles were incorporated into Aquivion® ionomer. The composite membranes presented high proton conductivity and increased stability to radical attack compared to non-modified Aquivion membranes, demonstrating the effectiveness of the approach based on radical scavenger immobilisation and release from clay nanocontainers.