Key points are not available for this paper at this time.
Anion-exchange-membrane water electrolyzers (AEMWEs) represent a highly promising technology for hydrogen production using renewable energy sources. To enable the broad adoption of AEMWEs, it is crucial to improve simple, scalable, and environmentally friendly synthetic methods for the development of transition metal-based electrocatalysts. Here, FeCo 3 /FeCoO x and Ni 1-x Co x /NiCoO x nanoparticles were obtained via a feasible two-step synthesis in an aqueous solution by cementation of aluminium powder. Both materials were tested as oxygen evolution reaction (OER) electrocatalysts comparing the electrochemical performance with commercial benchmark RuO 2 . The FeCo 3 /FeCoO x and Ni 1-x Co x /NiCoO x exhibited overpotentials of 288 mV and 296 mV for OER at a current density of 10 mA cm⁻², allowing a comparison between mass activity and geometric activity with RuO 2 . When integrated as anode electrocatalyst into a pilot-scale AEMWE, the materials were able to reach 2.10 V and 2.24 V (without iR-correction) at a current density of 1 A cm −2 (50°C), respectively. After acquiring the polarization curves, the AEMWE tests were extended for 100 hours with a continuous power profile, to have an initial assessment of the possible degradation trends for a future industrial application. The degradation rate resulted in 396 µV h −1 in the case of FeCo 3 /FeCoO x and no significant degradation for Ni 1-x Co x /NiCoO x . This study presents a straightforward and scalable approach to synthesizing earth-abundant electrocatalytic materials designed for high-efficiency OER.
Malaj et al. (Wed,) studied this question.