Dan Zhang, Huan Liu, Jin Liu, Yuejiang Shi, Bin Song, Yuyao Chen, Chenyu Li, Shuhan Li, Mingzhu Kang, Huaifang Zhang, Chong Zhang, Zhenyu Xiao, Yuanyuan Feng, Lei Wang
ABSTRACT Water electrolysis is a key technology for green hydrogen production, and the development of efficient, pH‐universal oxygen evolution reaction (OER) electrocatalysts is crucial for enhancing the performance of water electrolyzers. Herein, a highly efficient OER electrocatalyst consisting of ultrafine RuO 2 nanoparticles supported on boron‐doped carbon (RuO 2 /BC) is developed, achieving exceptional activity and durability. B‐doping strategy modulates the electronic structure of the carbon support, inducing strong metal‐support electronic interactions with the RuO 2 particles. This promotes the formation of abundant oxygen vacancies on the RuO 2 surface and optimizes the electronic state of Ru sites, enabling a pH‐dependent switching of the OER mechanism. Electrochemically, in alkaline OER, the adsorbate evolution mechanism endows the catalyst with an overpotential at 1000 mA cm −2 (η 1000 ) of only 419 mV, while in acidic OER, the lattice oxygen mechanism leads to an η 1000 of 418 mV. Furthermore, the catalyst demonstrates exceptional durability, maintaining stable operation for over 200 h in a membrane electrode assembly device. This work provides a novel support‐engineering strategy for designing high‐performance and highly stable Ru‐based OER catalysts.