Ultrafine cobalt-ruthenium alloy nanoparticles induced by confinement effect for upgrading hydrogen evolution reaction in all-pH range

Abstract The exploration of the inexpensive and efficient substitutes for platinum-based electrocatalysts is of great challenges for hydrogen evolution reaction (HER). Here, we presented a facile method to achieve highly active, cost-effective and stable HER catalysts, which are composed of ultrafine Co-Ru alloy nanoparticles embedded in heteroatom-free graphitic carbon (Co1-xRux/GC). The optimum catalyst with ruthenium content of 0.93 wt% exhibits remarkable HER activity and the excellent durability, low overpotentials of 14, 39 and 44 mV at -10 mA cm-2 are achieved in alkaline, neutral and acidic media, respectively, which can compete with those in commercial 20 wt% Pt/C and majority of the reported platinum-free catalysts. It has been validated that the confinement effect of SBA-15 induces the formation of ultrafine alloy nanoparticles for generating more active sites. The theoretical simulations reveal that Co-Ru alloy regulates hydrogen adsorption energy to the optimum level, thus resulting in high HER activity. This work provides new methods for the fabrication of ultrafine alloy nanoparticles for the electrocatalysis and other application.