Structure and morphology of aminopropyltriethoxysilane-modified TiO ₂ nano-particles derived from sol-gel processing of tetraethylorthotitanate

Amino-modified TiO₂ particles were derived from precursor mixtures of tetraethylorthotitanate and aminopropyltriethoxysilane (APTES) that both were dissolved in ethanol/water solution. Size, morphology, crystalline structures, and formation mechanism of the particles were discussed in terms of the APTES amount and the pH value in the solution. The addition of APTES resulted in amorphous amino-modified TiO2 particles. The low crystallinity in the final particles was attributed to the polar amino groups.