Structural and morphological Control of TiO2 nanoparticles by selective adsorption of organic molecules

Semiconducting nanocrystals with tailored shapes have been widely investigated in the past decades because of their many shape-dependant properties. Anatase, a metastable phase of the titanium dioxyde (TiO2), is one of the most interesting material in many applications, such as photocatalysis, photovoltaics, photo/electrochromics or sensors. [1]
In addition to an influence of the nanoparticles size, recent works on the anatase phase demonstrated the effect of the expressed surfaces nature on the nanoparticles photoreactivity. [2]
Sol-gel method has been used to obtain a wide range of anatase nanoparticles sizes and morphologies by the control of concentrations, ions in solution, solution acidity and aging parameters. [3]
In order to avoid the brookite phase often obtained with the anatase phase, microwave heating was efficiently used. Furthermore, conventional heating method has been compared with hydrothermal and microwave activated synthesis.
The precise morphological control has been achieved by selective adsorption of organic molecules during synthesis: different shapes of anatase nanoparticles have been synthesized. [4,5]. The influences of synthesis parameters and the organic molecules nature on the nanoparticles structure and morphology have been analysed with various techniques, such as XRD and HRTEM.