The Heterostructure of Ru2 P/WO3 /NPC Synergistically Promotes H2 O Dissociation for Improved Hydrogen Evolution.

Facilitating the dissociation of water and desorption of hydrogen are both crucial challenges for improving the hydrogen evolution reaction (HER) in alkaline media. Herein, we report the synthesis of heterostructure of Ru2 P/WO3 @NPC (N, P co-doped carbon) by a simple hydrothermal reaction using ruthenium and tungsten salts as precursors, followed by pyrolyzing under an Ar atmosphere. The Ru2 P/WO3 @NPC electrocatalyst exhibits an outstanding HER activity with an overpotential of 15 mV at a current density of 10 mA cm-2 and excellent durability in a 1.0 M KOH solution, outperforming state-of-the-art Pt/C and most reported electrocatalysts. Experimental results combined with density functional calculations reveal that the electron density redistribution in Ru2 P/WO3 @NPC is achieved by electron transfer from NPC to Ru2 P/WO3 and from Ru2 P to WO3 , which directly promotes the dissociation of water on W sites in WO3 and desorption of hydrogen on Ru sites in Ru2 P.