Study On The Composition,Structure And ESR Property Of Nanotube Sodium Titanate & Nanotube Titanic Acid

In this paper, a new kind of nanotubed material was prepared by the reaction of TiO2 with concentrated NaOH. The contents of Ti, Na,H2O and TiO2 in the nanotubed materials were analyzed by the way of Atomic Absorption, hydrogen peroxide colorimetry, and weight loss method, and its molecular formula was confirmed as Na2Ti2O4(OH)2. In dilute HC1 solution ( pH = 1 ), nanotubed Na2Ti2O4(OH)2 was converted to nanotubed H2Ti2O4(OH)2. XRD data show it belongs to C-base-centered orthorhombic system.Nanotubed titanic acid is thermally unstable, when T<300℃, the OH- groups in . the intralayer of nanotubed titanic acid occur dehydration, a symmetrical ESR signal appeared at g=2.003, and the signal intensity increased with treatment temperature, but crystalline structured and morphology of nanotubed titanic acid are unchangeable; when T>300℃, the OH- groups in the interlayer of nanotubed titanic acid occur dehydration, with the concentration of single-electron-trapped oxygen vacancy, oxygen vacancies occur interaction, they will form combination of flaw( (V0) ?n=2 or 3) , symmetrical ESR signal change into unsymmetrical, crystalline structure and morphology are destroyed.The influence of vacuum dehydration and visible light irradiation on ESR property of nanotube titanic acid was study. A symmetrical ESR signal appeared at g=2.003 in dark, which was assigned to be single-electron-trapped oxygen vacancy. The signal intensity increased with both treatment time and visible light irradiation time (A. -532nm). Under irradiation the signal intensity increased, till a steady state reached. After turning off the irradiation, the signal intensity decreased in dark but it cannot...