Synthesis and characterizations of nanometric-sized TiO2 powders as a photocatalyst for water splitting.
Nanometric-sized titanium oxide (TiO2) powders were synthesized through two emulsions method. In which two solutions of reverse emulsion, one containing Ti4+ chelated with citric acid/cellulose aqueous droplets and the other aqueous ammonia droplets, with the same water/oil (w/o) ratio are mixed together to form a slurry of titanium citrate precursor. Then the precursors were recovered and calcined to form TiO2 at various temperatures. The powders prepared from volume ratio of w/o at 1/100 had a relatively uniform and spherical with less aggregation. When the volume ratio of w/o was increased, the particle size had more aggregation and bigger. The particle sizes of powders obtained from volume ratio of 1/100 were estimated to be 6-8 nm. Finally, photocatalytic experiments for water splitting and producing hydrogen was examined in methanol solution by utilizing 65 mg nanometric-sized Pt (0.6 wt%)/TiO2 powder, and about 70 micromol hydrogen was produced in 6 h.
Yang
Wein-Duo
WD
Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan.
Hsieh
Ching-Shieh
CS
Wei
Tsong-Yang
TY
Chung
Zen-Ja
ZJ
Huang
I-Lun
IL