Preparation of Nano-TiO2 Powder by Polyacrylamide Gel Method

Polyacrylamide gel method is a new successful technique for preparing nanometer metallic oxide materials, such as alpha-Al2O3, ZnO and ZrO2. TiO2 made by this method, however, has not been reported. In this study, the nano-TiO2 powder was prepared using the novel method with TiCl3 as raw materials, and with acrylamide and N,N'-methylenediacrylamide as crosslinking agent. The TG showed that the optimization sintering process is that: the polyacrylamide gel was dried at 110 degrees C for 2 hour to obtain the xerogel, and then the grinded xerogel was sintered up to 450 degrees C, meanwhile, kept at 250 degrees C, 410 degrees C and 450 degrees C for 1 hour, respectively, to gain TiO2 particles. The grain size of TiO2 particles is smaller than 25 nm. And those particles are spherical approximately and have good distribution because of the hindering effect of space grid structure. Adding SO42- in the polyacrylamide gel process can maintain the content of anatase-TiO2 phase at higher sintering temperature. This may be explained that the SO42- can form coordination compound with Ti4+. And the coordination compound is prone to generate anatase-TiO2 with the burning out of SO42-, in which structure the adjacent two TiO6 hexahedrons share only one oxygen atom.