Preparation and SERS properties of Ag-deposited TiO2 hetero-structure nano-composites

A series of Ag-deposited anatase TiO2 nanobelts with different Ag contents were prepared by using ultraviolet-light reduction or/and seeding growth processes. The structure, morphology, Ag-deposition and SERS properties of the products were measured. The measurement results showed that the Ag nanoparticles reduced by ultraviolet-light irradiation, mainly in a diameter range of 10-50 nm, were deposited completely on the surface of TiO2 nanobelts, and the Ag content slowly increased with the increase of reduction times, significantly improving the coverage of Ag. Based on the product, the nano-composites with coverage of above 80% or almost 100%, were further obtained through seeding growth of Ag nano-particles by alternate addition of AgNO3 and sodium citric acid solution. The products remarkably exhibited surface-enhanced Raman scattering (SERS) activities with pyridine as a probe molecule, and the more the Ag nanoparticles, the stronger the SERS signal. © All Rights Reserved.