3D Hierarchical Carbon-Supported Ultrafine Ru Nanoparticles for pH Universal Hydrogen Evolution Reactions

Considering the much lower price of Ru compared with Pt, Ru-based catalysts are potential alternatives for the hydrogen evolution reaction, and developing a low-cost carrier and reducing the size of Ru nanoparticles are useful strategies to promote the usage of Ru-based catalysts. In this work, we report a facile method to prepare 3D hierarchical carbon with highly dispersed Ru nanoparticles using zinc citrate as the carbon precursor. Combined with the fast mass transport provided by the 3D hierarchical carbon and the high activity of ultrafine Ru nanoparticles, the prepared Ru-C catalyst exhibits remarkable hydrogen evolution reaction (HER) activity over a wide pH range, with overpotentials of 33, 50, and 90 mV in 0.5 M H2SO4, 1 M KOH, and 1 M phosphate-buffered saline, respectively, comparable to commercial Pt/C and surpassing many Ru-based electrocatalysts. This work provides an alternative route for preparing highly efficient HER catalysts based on the application of low-cost organic zinc salts as the carbon precursor, which is very attractive for large-scale applications.