过氧钛酸水热合成锐钛矿相二氧化钛纳米棒溶胶

Preparation of Anatase TiO_2 Nanorods Sol by the Hydrothermal Treatment of Peroxotitanium Acid

以双氧水溶解水合氧化钛沉淀得到的水溶性过氧钛酸水溶液为前驱体,用水热法制备了透明的锐钛矿相二氧化钛溶胶.用XRD、UV-Vis、PL、FT-Raman和TEM测定手段对溶胶中的晶粒进行了表征.结果表明:溶胶中二氧化钛纳米晶为锐钛矿相,晶粒为梭形棒状,并沿c轴定向生长,晶粒的平均直径小于10nm,其发射峰约在368nm处显示特征的带隙发光.水热时间的延长有利于晶粒"定向附着"生长,120℃时当水热时间由4h延长至24h时,可得到结晶完美、长径比接近10的二氧化钛纳米棒,并且其发光强度也有所增强.

Transparent anatase titanium dioxide sol was prepared by the hydrothermal treatment of the peroxotitanium acid （PTA） as precursor, PTA was synthesized by the reaction of hydrogen peroxide with the wellwashed wet titania precipitates. The TiO2 nanoparticles were characterized by XRD, UV-Vis, PL, FT-Raman and TEM. It is confirmed the nanoparticles are shuttlelike and in the anatase phase with average diameter less than 10nm, most of which grow along the c-axis. The TiO2 sol shows a band-gap emission at the wavelength of 368nm. Prolonging the hydrothermal time makes TiO2 nanoparticles align and form the longer nanorods with aspect ratio more than 10 via the oriented attachment mechanism. Moreover, more stronger emission is observed in the sol prepared for a prolonged hydrothermal duration due to the formation of more longer nanorods.