Published in Advanced Energy Materials, June 17 2025,15 (23), 2500554.
DOI: doi.org/10.1002/aenm.202500554.
Author(s): Yiming Zhu, Jiaao Wang, Gregor Weiser, Malte Klingenhof, Toshinari Koketsu, Shangheng Liu, Yecan Pi, Graeme Henkelman, Xinyue Shi, Jiayi Li, Chih-Wen Pao, Min-Hsin Yeh, Wei-Hsiang Huang, Peter Strasser, Jiwei Ma.
Abstract
New anodic electrocatalysts with high performance and cost-effectiveness at large current densities help advance the emerging anion exchange membrane water electrolyzer (AEMWE) technology. To this end, a ruthenium (Ru) single atoms and sulfur (S) anions dual-doped NiFe layered double hydroxides (Ru-S-NiFe LDH) catalyst is reported with remarkably low alkaline oxygen evolution reaction (OER) overpotentials, high mass activities and prolonged stabilities at high current densities. Inspiringly, the AEMWE performance on Ru-S-NiFe LDH is also superior to the NiFe LDH. In-depth mechanism investigations reveal that Ru single atoms not only act as the highly active sites, but also facilitate the conductivity of NiFe LDH. Meanwhile, S anions accelerate the electrochemical reconstruction of NiFe LDH to OER-active NiFeOOH and alleviate the over-oxidation issue on Ru active sites. Benefiting from these, Ru-S-NiFe LDH shows significantly enhanced OER activity and stability. Theoretical calculations further validate the decreased OER free energy difference brought about by the Ru single atoms and S anions dual-doping. This study offers a proof-of-concept that the noble metal single atoms and anions dual-doping is a feasible strategy to construct the promising 3d transition metal-based electrocatalysts toward the practical alkaline water electrolyzer.