On June 2, Associate Professor Zhang Wei from the Energy Research Institute published a paper titled "Spin crossover-driven diiron electrocatalyst boosts sustainable water oxidation" in the top international journal Nature Sustainability. Jingwei Tong from National Taiwan University and Wei Zhang from the Energy Research Institute are co-first authors, while Wei Zhang, Xiaocheng Zeng from City University of Hong Kong, and Haoming Chen from National Taiwan University are co-corresponding authors.

Against the backdrop of the dual-carbon goals, sustainable electrocatalytic CO₂ reduction and water oxidation serve as effective pathways to mitigate environmental issues. However, challenges such as the high overpotential and energy consumption of the anode oxygen evolution reaction (OER), strong reliance on scarce precious metals, and insufficient understanding of the performance and mechanisms of electroreduction catalysts limit their application. In this context, this paper reports an active diiron electrocatalyst, [Fe₂(μ-O)(μ-OH)(L1)₂], where L1 is a nitrogen-containing ligand. The catalyst demonstrates outstanding OER performance: achieving a turnover frequency of 20.2 s⁻¹ at 1.580 V, an ultralow overpotential of 184 mV at a current density of 10 mA cm⁻², and excellent stability over 1,000 hours. Through a spin crossover-driven dimerization mechanism, the catalyst transitions from a monoiron to a diiron active configuration, enhancing metal-ligand covalency. This facilitates the formation of the critical O-O intermediate for efficient dual-active-site OER catalysis, significantly improving both catalytic activity and stability. The study provides new insights for designing high-performance OER catalysts. It not only advances the understanding of green hydrogen production, dynamic active site evolution, and spin state regulation but also offers valuable mechanistic insights for designing molecular catalysts in sustainable electrochemical CO₂ reduction and green hydrogen evolution. This work highlights unified design principles that link water oxidation with CO₂ utilization, contributing to the transition toward a carbon-neutral energy system.