Synthesis of CdSe/SrTiO3 nanocomposites with enhanced photocatalytic hydrogen production activity

The photocatalytic hydrogen production has become one of the most promising strategies to solve the energy crisis and environmental pollution. Novel CdSe/SrTiO3 nanocomposites (average diameter ≈ 114.6 nm) with high photocatalytic activity are synthesized and used for visible light photocatalytic water splitting for hydrogen production. Through optimizing the concentration of CdSe QDs, CdSe/SrTiO3 nanocomposites exhibit increased visible light absorption and enhanced photocatalytic hydrogen evolution efficiency compared to SrTiO3 nanoparticles. The maximum H2 evolution amount reaches to 3350.53 μmol in 8 h by using CdSe/SrTiO3-3 as catalyst. Owing to the formation of heterojunction at the interface between CdSe and SrTiO3, the electrochemical impedance spectrum of CdSe/SrTiO3-3 exhibits the smallest arc radius and the photocurrent density of CdSe/SrTiO3-3 reaches to 0.26 μA cm−2. The photogenerated electrons are effectively separated and transferred and the recombination of electron-hole pairs is avoided, thus significantly improving the photocatalytic hydrogen production performance of CdSe/SrTiO3 nanocomposites.