| Summary: | 碩士 === 國立東華大學 === 材料科學與工程學系 === 94 === In this research, we have constructed a Flat-Flame MOCVD system to produce TiO2 nanopowder, which has superior photocatalytic decomposition capability. The photocatalytic reaction of TiO2 is to generate photo-induced electrons and holes and transform oxygen and water to powerful free radicals, to decompose all of the organic matters. The nanopowder, produced by the Flat-Flame MOCVD system has the advantage of high purity, low agglomeration and nano-range particle size resulting from reduced collision frequency between particles in reduced pressures. In our research, we will discuss the dependence of powder characteristics on several different parameters, for example, the flame condition, flame temperature, the concentration of precursor, residence time, and annealing temperature, for the control of particle size, doping, crystal structure and photocatalytic activity.
We have successfully synthesized the TiO2 nanopowder by controlling process parameters. The powder has much better photocatalytic decomposition capability than the commercialized product ST-01. Our nanopowder has bimodal distribution of particle size. One has mean value below 10 nm, and the other is in the range of 20 to 40 nm. The individual nanoparticle is a single crystal and the powder has a large surface area as high as 277 m2/g. In summary, the Flat-Flame MOCVD system is an effective method to synthesize photocatalytic TiO2 nanopowder.
|
|---|
