Facile Preparation of Ag-TiO2 Nanocomposite with Enhanced Photocatalytic Properties

摘要

For decades,photocatalytic semiconductor materials were regretfully limited to low-yield preparation method and poor catalytic efficiency although it has dramatically captured attention in sewage treatment applications.To expand this slim range of semiconductor catalysts,the nanocrystalline silver embedded in titanium dioxide(Ag-TiO2)heterojunction was prepared by means of facile mechanical milling technique capable of large-scale production,in terms of optimum Ag content.The as-obtained Ag-TiO2 nanocomposite particles were systematically characterized by means of X-ray diffraction technique,Raman spectra,X-ray photoelectron spectroscopy,transmission electron microscopy analysis,and UV-vis spectrophotometry.Results suggest that in comparison with pure TiO2 catalyst,Ag-TiO2 nanocomposite catalyst significantly enhanced photocatalytic activity for the degradation of methylene blue(MB),whereas its band gap decreased in view of the red-shift phenomenon.In terms of the experimental results,a mechanism was proposed to explain the enhancement of photocatalytic activity.Our findings offer a promising route towards the large-scale preparation of high-efficiency photocatalysts for commercial applications.