Ultrahigh-loading of atomically dispersed ruthenium on porous tungsten carbide by selective incorporation

Abstract

Atomically dispersed noble metal catalysts (ADNCs) drew attention due to the special properties of maximized metal usage and selectivity in electrochemical reactions. Despite many studies on ADMCs, technical limitations in synthesizing highly loaded ADCM still exist, because widely used conductive catalyst carbon supports cannot efficiently stabilize single metal sites. Herein, we report ultrahigh loading of atomically dispersed ruthenium (~15 wt.%) on porous tungsten carbide (WxC) support. Hydrophobic Ru precursor is selectively incorporated into the PS domain of the PS-b-PEO template. PS domain provides a physical barrier and in-situ formed carbon gases during 900 ℃ heat treatment that prevents particle aggregation. Simultaneously formed tungsten carbide at high temperature provides ample anchoring sites and strongly attracts Ru, stabilizing atomically dispersed Ru atoms. The as-synthesized catalyst showed a superior overpotential of 12 mV at 10 mA cm$^{-2}$ in alkaline hydrogen evolution reaction. This novel and facile ADMC design strategy overcame the general problem of low synthesis temperature and low metal loading, offering a promising route for synthesizing ADMCs with ample active sites.