Strong Photothermal Effect of Plasmonic Pt Nanoparticles for Efficient Degradation of Volatile Organic Compounds under Solar Light Irradiation

Recently, the photothermal effect of plasmonic nanometals has been increasingly studied in the biomedical field but few in the environmental remediation, e.g., the elimination of volatile organic compounds (VOCs). In this article, the Pt/γ-Al2O3 has been synthesized with the tunable optical properties for efficient toluene decomposition under the full solar spectrum irradiation because of the plasmonic photothermal effect of the Pt nanoparticles (NPs), which simultaneously serve as the light absorber and the catalytically active site. Transmission electron microscope (TEM) images show that Pt NPs with average diameter around 1 nm are well dispersed on the γ-Al2O3. UV–vis absorption spectra of the Pt/γ-Al2O3 exhibit the strong absorbance in the wavelength range 200–2500 nm due to the surface plasmon resonance (SPR) absorption of Pt NPs. As a result, the 1.81 Pt/γ-Al2O3 shows a highly efficient catalytic activity with toluene conversion of 87% and CO2 yield of 84% under a solar irradiation intensity of 320 mW/cm2 as well as a decent stability upon a continuous running for 30 h. This work highlights that Pt/γ-Al2O3 plasmonic catalyst shows great promise for VOCs elimination through the plasmonic photothermal effect.