One-dimensional gold-doped monoclinic iridium oxide nanoribbons for high-efficiency acidic oxygen evolution reaction

Proton exchange membrane water electrolysis (PEMWE) stands as the predominant technique for the production of high-purity hydrogen. However, it is confronted with a significant impediment due to the sluggish kinetics inherent to the anodic oxygen evolution reaction (OER). This limitation has spurred the search for catalysts that exhibit both high activity and durability in facilitating the OER. One-dimensional (1D) metastable-phase iridium oxide (IrO2) has emerged as a promising OER catalyst, yet its catalytic activity and stability have hitherto fallen short of the stringent requirements for industrial-scale applications. Here, by leveraging a heteroatom doping strategy, we have successfully synthesized 1D gold-doped IrO2 monoclinic nanoribbons (Au-doped IrO2NRs), further optimizing the electrochemical activity and durability of IrO2 nanoribbons under acidic conditions. Au-doped IrO2NRs not only preserve the crystal structure characteristic of monoclinic IrO2NRs, but also exhibit improved catalytic performance. Under an acidic environment, Au-doped IrO2NRs reach a low overpotential of 180 mV at a current density of 10 mA cm-2, a low Tafel slope of 40.6 mV dec-1, and a durable stability of 160 h at 10 mA cm-2. When integrating into the anode compartment of a practical PEMWE system, Au-doped IrO2NRs sustained operation for more than 500 h at 60 degrees C. These results highlight the capacity of Au-doped IrO2NRs to promote the performance and endurance of PEMWE, which in turn supports the wider implementation of hydrogen as a sustainable energy carrier.