Photocatalytic Co2 Reduction And Hydrogen Production Over Pt/Zn-Embedded Beta-Ga2o3 Nanorods

Gallium oxide has shown a potential catalyst application in energy and environment. Herein, beta-Ga2O3 and Zn-embedded beta-Ga2O3 nanorods were prepared by hydrothermal method and post-thermal annealing process. The physicochemical properties were examined by scanning electron microscopy, electron transmission microscopy (TEM), Auger elemental mapping, X-ray diffraction crystallography, UV-visible absorption, Raman, Fourier-transform infrared, and X-ray photoelectron spectroscopy. Photocatalytic CO2 reduction products over beta-Ga2O3 nanorods in gaseous CO2/H2O atmosphere were found to be CO, CH4, and H-2 with rates of 0.055, 0.058, and 14.8 mu mol.g(-1).h(-1), respectively under UVC irradiation confirmed by gas chromatography. Upon 5 mol% Zn-embedding, the rates of CO, CH4, and H-2 were observed to be 1.49, 0.24, and 0.19 mu mol.g(-1).h(-1), respectively. The CO and CH4 yields were increased by 27 x and 4x, respectively. CH3OH was barely detected for Zn or Pt-only embedded beta-Ga2O3, but significantly increased to 0.19 mu mol.g(-1).h(-1) upon Pt/Zn(5 mol%)-cocatalyst embedding. The photocatalytic hydrogen production was increased by 3.6 x and 27.4 x upon Pt/Zn-cocatalyst embedding, compared with those of Zn-embedded and bare beta-Ga2O3, respectively. The Pt/Zn-cocatalyst embedding was found to show 2.5 x higher rate than the Pt-only embedding. The rate reached to 404.5 mu mol.g(-1).h(-1) for Pt(0.5 nm)/Zn(2 mol%)/beta-Ga2O3. The unique demonstration tests provide precious information for the improvement of Ga2O3-based CO2 reduction and hydrogen production catalysts.