Effect of anion exchange ionomer content on electrode performance in AEM water electrolysis. (30th October 2020)

• Record Type: Journal Article
• Authors: Faid, Alaa Y.; Xie, Lin; Barnett, Alejandro Oyarce; Seland, Frode; Kirk, Donald; Sunde, Svein
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 53(2020)
• Page Start: 28272
• Page End: 28284
• Publication Date: 2020-10-30
• Subjects: Anion exchange ionomer -- Electrode potential -- Ni-based catalysts -- AEM water Electrolysis; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.07.202
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Anion exchange membrane water electrolysis (AEMWE) has acquired substantial consideration as a cost-effective hydrogen production technology. The anion ionomer content in the catalyst layers during hydrogen and oxygen evolution reaction (HER and OER) is of ultimate significance. Herein, an in-situ half-cell analysis with reference electrodes was carried out for simultaneous potential measurements and identification of the influence of the anion exchange ionomer (AEI) content on anode and cathode performance. The measured half-cell potentials proved the influence of AEI content on the catalytic activity of HER and OER, which was supported by the rotating disk electrode (RDE) measurements. Cathode overpotential of Ni/C was not negligible and more affected by the AEI content than anode with the optimized AEI content of 10 wt% while NiO anode OER overpotential was independent of the AEI content. For the same AEI content, PGM catalysts showed higher electroactivity than Ni-based catalysts for HER and OER and the cathode catalyst's intrinsic activity is of high importance in the AEM electrolysis operation. Post-mortem analysis by SEM mapping of both AEI and catalyst distributions on the electrode surface showed the effect of AEI loading on the catalyst morphology, which could be related to the electrode performance. Highlights: The anion exchange ionomer (AEI) content affects the electrolyzer performance. Cathode overpotential of Ni/C was not negligible compared to the NiO anode. The Ni/C cathode overpotential is more affected by AEI content than NiO anode. Electrode performance could be related to AEI effect on catalyst layer morphology.