Promoted Alkaline Hydrogen Evolution Reaction Performance of Ru/C by Introducing TiO₂ Nanoparticles

Abstract

Abstract Higher water dissociation (Volmer step) energy barrier leads to the sluggish alkaline hydrogen evolution reaction (HER) rate. Since hydrophilic TiO 2 can reduce water dissociation barrier while the widely studied Ru has nearly zero hydrogen adsorption Gibbs free energy, the combination of TiO 2 and Ru/C might collectively enhance Volmer and Heyrovsky/Tafel step and finally promote HER performance. Herein, Ru/C−TiO 2 with average size of 3.6 nm for Ru was synthesized by a two‐step process. It presented superior alkaline HER activity with η 10 of 44 mV, better than that of Ru/C (107 mV), Pt/C (84 mV) and C−TiO 2 with negligible activity. The prominent HER performance was due to synergistic effect between TiO 2 and Ru, which greatly expedited water dissociation for intermediate hydrogen production and the following electrochemical hydrogen desorption for producing H 2 . This work combines specific active sites for different elementary steps and then boosts alkaline HER performance, which provide a guide for designing efficient and stable HER electrocatalyst.