Abstract:

The nanocomposite Ag/TiO2-ZrO2 possessing high photocatalytic activity was prepared by the sol-gel method combined with temperature-programmed treatment in the presence of the triblock copolymer surfactant EO20PO70EO20 (P123) followed by extraction. The phase composition, structures and morphologies of the nanocomposite Ag/TiO2-ZrO2 were well-characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), N2 adsorption-desorption tests and scanning electron microscopy assisted X-ray energy dispersive spectroscopy (SEM-EDS). Results showed that the silver species in the nanocomposite Ag/TiO2-ZrO2 was metallic Ag0. Moreover, the composite had bimodal pore systems, an orderly distribution of particles and good structure. The average pore diameter was ca 3.6 and 9.0 nm. The microwave assisted photocatalytic degradation of methyl orange on Ag/TiO2-ZrO2 in an aqueous solution was carried out to investigate the catalytic activity. After extraction, the photocatalytic activity under microwave irradiation was found to be more efficient than that under UV irradiation and methyl orange degraded by 81.5% within 90 min. This degradation behavior was better than that of Degussa P25 and TiO2-ZrO2.

Key words: Sol-gel, Ag/TiO2-ZrO2, Photocatalysis, Microwave, Methyl orange