Abstract

TiO_2 nanopowder was synthesized by chemical vapor condensation (CVC) process and its photocatalytic property depending on microstructure was considered in terns of decomposition rate of organic compound. In order to control microstructure of TiO_2 nanopowder such as particle size and degree of agglomeration, precursor flow rate representing number concentration was changed as a process variable. In TEM observation, spherical TiO_2 nanoparticles with average size of 20 nm showed gradual increases in particle size and degree of agglomeration with increase of precursor flow rate. Also decomposition rate of organic compound increased with decreasing precursor flow rate. Thus, it was concluded that photocatalytic property was enhanced by targe surface area of disperse TiO_2 nanoparticles synthesized at lower precursor flow rate condition in CVC process.

• Keywords: TiO_2 nanopowder;Chemicla vapor condensation;Photocatalytic property;Dispersion;