Wenxiang Zhu, Jing Zhou, Mengjie Ma, Hengjie Liu, Fan Liao, Hui Huang, Chang-Yang Kuo, Yunxiang Lin, Chih-Wen Pao, Yu-Chung Chang, Shu-Chih Haw, Su-Yang Hsu, Jin-Ming Chen, Meng Ni, Yang Liu, Mingwang Shao, Zhiwei Hu, Zhenhui Kang, Xiaoqing Huang, Qi Shao
The acidic oxygen-evolution reaction is intrinsically sluggish and requires large overpotentials, creating a key bottleneck for proton-exchange membrane water electrolysis technology. Here we show an edge-sharing single-layer oxide, 1T-phase ruthenium oxide (1T-RuO2). The edge-sharing configuration enables parallel alignment of ruthenium 4d orbitals across adjacent RuO6 octahedral clusters, facilitating intersite electron transport, in contrast to conventional rutile-type RuO2 with corner-/edge-sharing structures. 1T-RuO2 exhibits high acidic oxygen-evolution reaction activity with a low overpotential of 77 mV at 10 mA cm-2. It also delivers a mass activity of 3 , 743 . 43 A g Ru - 1 and a turnover frequency of 23.99 s-1 at 1.50 V versus the reversible hydrogen electrode, exceeding those of rutile-RuO2 and showing highly competitive performance under the described experimental framework. In addition, 1T-RuO2 maintains a current density of ∼2.9 A cm-2 at a cell voltage of 1.70 V for over 1,100 h in a proton-exchange membrane water electrolyser.