Synthesis of TiO_(2) nano-particles and their photocatalytic activity for formaldehyde and methyl orange degradation

TiO2 nano-particles were synthesized by sol-gel technique and characterized by X-ray diffractometer(XRD)and transmission electron microscope(TEM).Their photo-catalytic activities for formaldehyde(FA)and methyl orange(MO)degradation were tested using degradation rate(η)as an evaluation index.Based on the orthogonal test results,the optimal condition for TiO_(2) preparation was obtained.Results showed that particle sizes were in the range of 10–40 nm,and that prepared TiO_(2) had better photocatalytic activity than P25.A simplified model was developed to evaluate the apparent quantum efficiency(Φapp)of this photocatalytic reaction system.