Synergetic Oxidized Mg and Mo Sites on Amorphous Ru Metallene Boost Hydrogen Evolution Electrocatalysis
Fenyang Tian, Shuo Geng, Menggang Li, Longyu Qiu, Fengyu Wu, Lin He, Jie Sheng, Xin Zhou, Zhaoyu Chen, Mingchuan Luo, Hu Liu, Yongsheng Yu, Weiwei Yang, Shaojun Guo
Abstract
Abstract Ruthenium (Ru) is considered as a promising catalyst for the alkaline hydrogen evolution reaction (HER), yet its weak water adsorption ability hinders the water splitting efficiency. Herein, a concept of introducing the oxygenophilic MgO x and MoO y species onto amorphous Ru metallene is demonstrated through a simple one‐pot salt‐templating method for the synergic promotion of water adsorption and splitting to greatly enhance the alkaline HER electrocatalysis. The atomically thin MgO x and MoO y species on Ru metallene (MgO x /MoO y ‐Ru) show a 15.3‐fold increase in mass activity for HER at the potential of 100 mV than that of Ru metallene and an ultralow overpotential of 8.5 mV at a current density of 10 mA cm −2 . It is further demonstrated that the MgO x /MoO y ‐Ru‐based anion exchange membrane water electrolyzer can achieve a high current density of 100 mA cm −2 at a remarkably low cell voltage of 1.55 V, and exhibit excellent durability of over 60 h at a current density of 500 mA cm −2 . In situ spectroscopy and theoretical simulations reveal that the co‐introduction of MgO x and MoO y enhances interfacial water adsorption and splitting by promoting adsorption on oxidized Mg sites and lowering the dissociation energy barrier on oxidized Mo sites.