TiO2 photocatalyst with single and dual noble metal co-catalysts for efficient water splitting and organic compound removal

Abstract

Photocatalysts can be used both for air cleaning and solar energy harvesting through water splitting. However, pure TiO2 photocatalysts are often inefficient and therefore co-catalysts are needed to improve the yield. To achieve this goal, we prepared TiO2 and deposited Pt, Ir and Ru co-catalysts on its surface. Two base TiO2 nanoparticles were used: P25 and rutile TiO2 synthesized via hydrothermal method. Co-catalysts were deposited by wet impregnation technique using single element and a combination of two elements (Pt and Ir or Pt and Ru), followed by annealing in either air or H2/Ar. Annealing in reducing atmosphere increased the photocatalytic activity of oxidation of isopropanol compared to annealing in air. We demonstrated a clear influence of the co-catalysts on the photocatalytic degradation of isopropanol and on electrochemical water-splitting reaction. The platinum-containing samples showed the best HER activity.