Preparation and catalytic properties of platinum dioxide nanoparticles: A comparison between conventional heating and microwave-assisted method

Using platinum chloride, sodium hydroxide, sodium acetate, and polyvinylpyrrolidone as starting materials, platinum dioxide nanoparticles with small particle diameter and narrow distribution were prepared by microwave irradiation and conventional heating, respectively. UV-vis spectrophotometer was used to trace the hydrolytic decomposition of platinum chloride and the formation of platinum dioxide nanoparticles. X-ray powder diffraction and transmission electron microscopy were employed to characterize the crystalline structure and the morphologies of the obtained nanoparticles. Gas chromatography was performed to investigate their catalytic properties for hydrogenation of cyclohexene. The results revealed that (i) the obtained nanoparticles have the same crystalline structure; (ii) the nanoparticles obtained by microwave irradiation were smaller and more narrowly distributed than those obtained by conventional heating; (iii) the activation time of the catalyst markedly influences the catalytic activity; (iv) the particles obtained by microwave irradiation showed higher catalytic activity than those obtained by conventional heating for hydrogenation of cyclohexene. (C) 2009 Elsevier B.V. All rights reserved.