Preparation And Characterization Of Nano-titania

Large specific surface area titania was synthesized by the sol-gel and the hydrothermal method. First, nanotitania was synthesized by the sol-gel method, using laurylamine as the template and titanium tetrabutoxide (TBOT) as the precursor. The synthesized titania was anatase with the specific surface area of 30m2/g, the average pore size of 6.77nm, and the average pore volume of 0.021cc/g. Then cetyltrimethylammonium bromide (CTAB) was used as the template, triethanolamine as the solvent, and TBOT as the precursor to synthesize titania by the sol-gel method. The obtained anatase nanotitania has the specific surface area of 50m2/g,the average pore size of 19.87nm,and the average pore volume of 0.26cc/g。Then, anatase titania was synthesized by the hydrothermal method using CTAB as the template, 2-butanol or ethanol as the solvent, respectively. The obtained titania had the specific surface area of 242.4m2/g, the average pore size of 3.47nm, and the average pore volume of 0.21cc/g, using ethanol as the solvent with the reaction at 60℃for 12h. The calcined titania had the specific surface area of 31.32m2/g, the pore size of 10.08nm, and the pore volume of 0.079 cc/g. When the reaction was hold at 80℃for 12h, the anatase titania showed nanorod structures, and had the specific surface area of 218.3m2/g, the pore size of 3.49nm, and the pore volume of 0.19cc/g. However the specific surface area changed to 60.78 m2/g, the pore size changed to 8.93nm, and the pore volume to 0.14 cc/g after calcination.Finally, chitosan(CS) and CS-CTAB were used as the template to synthesize nanotitania by the hydrothermal method. The obtained titania had the specific surface area of 432.36 and 393.66m2/g, the pore sizes of 3.33 and 3.72nm, and the pore volumes of 0.36 and 0.37cc/g, when the template was CS or CS-CTAB, respectively. Additionally, titania doped silica (mol ratio of titaia to silica was 1:1) using CS and CS-CTAB as the template was synthesized by the hydrothermal method. The specific surface area was increased up to 562.92m2/g. While after calcinations, the specific surface area were 538.86 and 325.28m2/g, the average pore sizes were 3.28 and 3.51nm, and the average pore volume were 0.458 and 0.13cc/g , respectively.