Pt Nanoparticle-Decorated CdS Photocalysts for CO₂ Reduction and H₂ Evolution

It is important to effectively use nanoscale noble metal cocatalysts for photocatalysis. A polyol reduction method is a promising method to prepare nanoscale noble metal nanoparticles, but only a few studies about synthesis of noble metal/semiconductor nanoparticle photocatalysts are reported. Its influence on the photocatalytic reaction has not yet been fully studied, especially on electron/hole-induced reactions. Also, the key point to fully realize the potential of the polyol reduction method is unclear. Herein, we systematically studied the effect of polyol reduction from the viewpoint of photocatalysis in different kinds of photocatalytic reactions including electron-induced CO2 reduction, H2 evolution, and hole-induced pollutant degradation. We find that samples obtained by the polyol method are better than those obtained by the traditional photoreduction method. The reason for enhancement and the chemistry in the formation of nanosized noble metal deposition are fully analyzed. We also discover that in situ deposition is of great significance to obtain a high-efficiency nanoscale noble metal/semiconductor system.