Formation of Anisotropic Nanostructures on Rutile TiO2(110) Surfaces and Their Photo-Absorption Properties

Enhancement of absorption properties in nanostructures of rutile TiO2, fabricated through an ion beam sputtering process, are reported here. The nanostructures are anisotropic in nature, being elongated along the [001] direction. With increasing fluence, the anisotropy of the nanostructures increases. Their width along [11¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{1}$$\end{document}0], however, is constrained and does not grow proportionally. The results indicate that the asymmetric diffusion of mobile species, created by preferential sputtering, on the rutile TiO2(110) surface plays a crucial role in defining the nanostructure morphology as well as the photo-absorption properties. An enhanced photo-absorption response from TiO2 nanostructures was also observed here. The results were obtained in the absence of any dopant material.