Just Accepted Articles have been posted online after technical editing and typesetting for immediate view. The final edited version with page numbers will appear in the Current Issue soon.
Developing efficient and durable electrocatalysts that minimize or eliminate Ir usage is essential for large-scale hydrogen production through proton exchange membrane water electrolysis. In this work, two IrOx–Co3O4?catalysts with distinct interfacial configurations were constructed to clarify the effect of structural coupling on activity and stability. The embedded IrOx–Co3O4?was prepared via a galvanic replacement–induced embedding process, while the surface-exposed IrOx–Co3O4?was obtained through photo-reduction deposition. Structural analyses confirm the formation of strong Co–O–Ir linkages in embedded IrOx–Co3O4, in contrast to discrete surface IrOx?nanoparticles in the exposed sample. Electrochemical measurements show that exposed-IrOx?delivers a lower overpotential of ≈ 331 mV at 10 mA cm-2?but suffers from fast Ir dissolution, whereas embedded IrOx?maintains stable operation with a voltage of 1.78 V at 1 A cm-2?for over 200 h in a PEM cell.?In-situ?Raman and DEMS results reveal that embedded IrOx?follows a dominating classical adsorbate-evolution mechanism (AEM), while exposed IrOx–Co3O4?involves a lattice-oxygen-mediated mechanism (LOM), leading to its inferior stability. This work highlights that strengthening Co–O–Ir interface effectively suppresses Ir loss and provides a general strategy for designing robust Ir-based catalysts for acidic water electrolysis.
Address: Fuzhou High & New Technology Industrial Zone, Shangjie, Minhou, Fuzhou, Fujian 350108, China
Tel: (86)-591-63173769, 63173770
E-mail: cjsc@fjirsm.ac.cn
CN 35–1112/TQ, ISSN 0254–5861, Online ISSN: 2949-768X Copyright @ 2022 Chinese Journal of Structural Chemistry-www.Chinese Journal of Structural Chemistry.net. All Rights Reserved 閩ICP備2022002645號-1