Modification of TiO2 surface for improved light fastness

Abstract

Introduction: Rutile TiO2 dioxide particles were modified with P2O5 treatment for improving its UV light fastness and the characteristics are studied using different techniques. The investigation aimed at improving the light fastness of the TiO2 particles by surface modification with P2O5 and optimizing its content for best performance. The coating of different inorganic oxides such as SiO2, Al2O3, P2O5, etc. were confirmed by atomic absorption spectroscopy. Microscopic evaluation was employed to evaluate the surface morphology of modified TiO2. The specific surface area was estimated using BET method. Effect of the surface modification with oxides on electrokinetic properties and zeta potential is appraised. Changes in the pigmentary properties on UV exposure are determined as a measure of light fastness. Results: The light fastness of the modified samples is superior to commercial TiO2 pigments. The dispersion and pigmentary characteristics of the P2O5 modified samples have approached the commercial rutile TiO2 pigment standards. The reducing strength values indicate good dispersion characteristics of the P2O5 modified samples. Conclusion: The light fastness of TiO2 particles can be improved considerably on imparting the coating of P2O5 along with Al2O3.