Economical and versatile way to prepare TiO2 nanostructures and their safe applications

Nanostructures including particles, rods, wires, belts, cages, walls, flowers and rings of almost all materials have been reported to be harmful and toxic [1]. Nanomaterials made from the urea, polyethylene glycol, polyvinylpyrrolidone, polytertrafluoethylene or PTFE, showed even more dramatic effects. To address this burning and urgent issue, we have made a small breakthrough in preparation of nanomaterials including the present one in discussion. Titanium oxide (TiO₂) has many applications in the field of sensors, new type of solar cells, electrochromic devices, antifogging and self cleaning surfaces. It has also been shown to be useful for the destruction of micro-organisms such as bacteria and viruses, the inactivation of cancer cells, the control of odors, the fixation of nitrogen and the cleanup of oil spills [2]. It has been reported that the different methods for the synthesis of titanium dioxide results in products with different structures (anatase or rutile), crystallinity and contaminants. A detailed study has revealed that all reported methods involve multistep processes and frequent use of harmful additives [3]. In addition, the pathways suggested involve environmentally malignant chemicals which are toxic and not easily degraded in the environment. We report an alternative approach for titanium oxide (TiO₂) nanocapsules through an economic and environmentally benign route of varying size ranging from 10-50nms as shown in Figure 1. The approach is based on a simple reaction of titanium foil and water at ~110°C without use of any toxic additives or organics. The formation of TiO₂ nanoparticles on titanium foil in the presence of water can be explained by chemical reactions and schematically shown in Figure 2. Since only pure water which is regarded as a benign solvent is used during the preparation of nanoparticles, we believe that the products so produced are biocompatible and bio-safe and can be readily used f- r medical applications. In addition, the method is simple, straightforward, fast, economical, environmentally benign, involves green chemistry, which can make it suitable for scale large production. The prospects of the process are bright and promising. The approach described above is expected to show marvelous results.