Hydrothermal preparation of Ag-TiO2 nanostructures with exposed {001}/{101} facets for enhancing visible light photocatalytic activity

Abstract

Nano-composite materials of Ag nanoparticles dispersed TiO2 nanocubes with exposed {001}/{101} crystal faces were fabricated mainly via a flexible one-step method of hydrothermal treatment with different content of Ag from 1 up to 3mol%. Prepared photocatalysts were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscopy, UV–vis absorption spectroscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. These analysis was carried out for understanding the contribution of different content of silver for enhancing the photocatalytic activity of TiO2 nanocubes. Prepared silver nanoparticles had small particle size and grafted to the {101} crystal face of TiO2 with the role of template control agent and linking agent. The photocatalytic performance of Ag-TiO2 nanocubes were researched via Rhodamine B dye removal under visible light irradiation ( ≧420nm). Ag-TiO2 composite materials with the content of 2mol% Ag showed the best photocatalytic activity for degradation of Rhodamine B, which was five times more than bare TiO2 and associated with the localized surface plasmon resonance (LSPR) propelled effect. The mechanism by which silver enhanced the photocatalytic activity of TiO2 was also demonstrated.