Chemical modification of titanium isopropoxide for producing stable dispersion of titania nano-particles

Stable colloidal TiO2 nano-particles are synthesized through the controlled hydrolysis of chemically modified titanium (Ti) isopropoxide with acetylacetone and acetic acid whereas ammonium salts of poly(acrylic acid) is used as a dispersing agent. Acetylacetone and acetic acid used as chelating ligand to retard the hydrolysis and condensation rates. The process is found promising for producing homogeneous aqueous phase colloidal dispersion of TiO2 particles. Fourier transformed infrared and nuclear magnetic resonance spectra reveal the formation of monodentate bridging of ligands with Ti-isopropoxide. UV-Vis spectroscopy confirms the effective adsorption of poly(acrylic acid) within the modified Ti precursor. Zeta potential of modified titanium isopropoxide precursor is measured to understand its stability in different pH. The thermal stability of the precursors modified with different chelating ligands and dispersing agent has been studied using thermo-gravimetric in conjunction to differential thermal analysis (TG-DTA). Phase formation behavior and the morphological features of the synthesized particles are studied using X-ray diffraction and electron microscopy techniques. The sizes of the anatase phase particles are found in the range of 12-20 nm. (C) 2014 Published by Elsevier B.V.