Preparation of carbon coated hyperdispersed Ru nanoparticles supported on TiO2 HER electrocatalysts by dye-sensitization

Abstract

Hydrogen production by water-splitting is a very promising strategic energy technology and one of the most important means to obtain green hydrogen. It is of great practical significance to develop cheap and efficient electrocatalysts to replace Pt. Herein, we use the dye-sensitization strategy to load hyperdispersed Ru nanoparticles on the TiO₂ surface, and then use cheap glucose for carbon coating to improve the conductivity of the material, so as to obtain an efficient HER catalyst C/Ru/TiO₂. On the one hand, dye molecules can be firmly bonded to the surface of TiO₂ through carboxyl groups, and on the other hand, their large steric effect can effectively inhibit the aggregation of molecules, so ruthenium nanoparticles formed after pyrolysis can be uniformly distributed on the surface of TiO₂. Carbon coating also effectively solves the problem of poor conductivity of TiO₂ as a support. C/Ru/TiO₂ shows excellent catalytic performance for HER. In 0.5 M H₂SO₄, the overpotential is 69 mV at 10 mA cm⁻² and the Tafel slope is only 70 mV dec⁻¹. In 1 M KOH, the overpotential is only 51 mV at 10 mA cm⁻² and the Tafel slope is only 68 mV dec⁻¹. The dye-sensitization strategy makes it easy to realize the loading of hyperdisperse metal nanoparticles on the support surface.