Synthesis and Characterization of New Bimetallic Pt,Ag/SBA-15 Materials

Abstract

This paper reports, for the first time, synthesis and characterization of new bifunctional materials containing platinum and silver ions deposited on mesoporous ordered silica SBA-15. Both types of ions were incorporated on silica surface during adsorption from water solutions containing various amounts of dissolved tetraamineplatinum(II) dichloride and diamminesilver(I) hydroxide or tetraamineplatinum(II) dichloride and diamminesilver(I) chloride complexes. The silanol groups on silica surface play important role in adsorption mechanism and one of the most commonly used technique for their characterization is photoacoustic spectroscopy. This technique provides clear evidence of successfully incorporation two types of precious metal ions (Pt and Ag) on SBA-15 surface. The decomposition process of absorbed complexes was investigated according to high temperature in helium. The products of decomposition were analyzed by mass spectrometer. Obtained results show that decomposition temperature of platinum and silver complexes are quite vary. Similarly mechanisms of decomposition of ligands from silver and platinum complexes are also different. Moreover, the structural and chemical properties of Pt,Ag-SBA-15 samples were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS).