Preparation of platinum nanoparticle and its catalytic activity for toluene oxidation

Colloidal Pt nanoparticles are prepared using H ₂PtCl ₆ as a precursor, polyvinylpyrrolidone (PVP: molecular weight = 10,000 and 40,000) and hydrogen as a stabilizing agent and a reducing agent, respectively. The amounts of the precursor and the stabilizing agent and the molecular weight of PVP have an effect on the formation of Pt nanoparticles. Supported Pt catalyst (CSPt) is prepared from colloidal Pt nanoparticles and γ-Al ₂O ₃. Another supported Pt catalyst (ISPt) is prepared by using the conventional incipient wetness impregnation method with an aqueous H ₂PtCl ₆ solution and γ-Al ₂O ₃. The catalytic activities of CSPt and ISPt catalysts are compared for VOC (toluene) oxidation. Transmission Electron Microscopy (TEM), UV-vis, X-ray diffraction (XRD) and temperature programmed reduction (TPR) are used to characterize CSPt and ISPt catalysts. The experimental results reveal that the catalytic activity of CSPt is superior to that of ISPT.