Manipal University Jaipur, India
Metal/heterometal oxides nanostructures play an important role in materials science applications. Several applications such as photocatalysis, in waste water treatment, lithium ion batteries, microelectronic circuits, solar cells, as sensors, as piezoelectric devices have been reported in literature. Earlier approach to synthesis was through solid state chemistry route, but in the recent years alternate approach using solution techniques have emerged, including coprecipitation, sol-gel process, hydrothermal processing, and solvothermal methods for fabrication of oxides nanostructures. Among these, sol-gel is a versatile method for the growth of nanostructures, such as nanorods, nanowires, nanobelts and hierarchical nanostructures, due to its simplicity, easy handling process and capability to control over grain size. Metal alkoxides are commonly used precursors for the synthesis of oxides nanostructures. The modification in metal alkoxides i.e. substitution of alkoxo group by chelating ligands such as oximes, β-ketones, schiff’s base, glycerols, etc.; changes electronic environment of the precursor, which affects the kinetics of hydrolysis as well as condensation reactions, leads to altered morphology and functionality of oxides nanostructures. The introduction of modifiers not only generates steric effects, but also increase the gelation time and maintained the viscosity of the sol.
The present authors have experimented to modify the precusors of aluminum and titanium alkoxides, and also studied the effect of precursor chemistry on the morphology and size of the nanostructured metal/heterometal oxides by sol-gel technique. The paper presents the approach to modify the precusors of aluminum and titanium alkoxides, leading to modified nanoparticles with altered morphology. The nano-structures so obtained were found to possess better antiscratch and anti-corrosive properties, making them an attractive possibility for surface protective coatings