Synthesis and photocatalytic activity of TiO2 nanostructures by sequential implantation of Ti and Ag ions into SiO2

Abstract

TiO2 nanostructures are synthesized in SiO2 by single implantation of Ti ions and sequential implantation of Ti and Ag ions with subsequent annealing in N2 atmosphere. The surface morphology, structure, and optical and photocatalytic properties of the fabricated TiO2 nanostructures are investigated. The experimental results indicate that the synthesized nanostructures are attributable to TiO2 in the anatase phase as annealing temperature reaches 700 ℃. However, further increase in the annealing temperature leads to the transformation of anatase TiO2 into rutile TiO2. Compared with the samples implanted only with Ti ions, the additional implantation of Ag ions promotes thermal growth of the TiO2 nanostructures and reduces their initial formation temperature and optical band gap. Moreover, results of the photocatalytic experiments demonstrate that additional Ag ion implantation improves the photocatalytic activity of the fabricated TiO2 nanostructures. The possible mechanisms for improvement in photocatalytic activity due to the presence of additional Ag ions is discussed based on measurements of photoluminescence and X-ray photoelectron spectroscopy.

Keywords

• ion implantation
• tio2 nanostructures
• phase transformation
• photocatalytic activity