Acta Chimica Sinica ›› 2013, Vol. 71 ›› Issue (01): 93-101.DOI: 10.6023/A12090724 Previous Articles     Next Articles



赵斌a, 林琳a, 陈超a, 柴瑜超b, 何丹农a,b   

  1. a 纳米技术及应用国家工程研究中心 上海 200241;
    b 上海交通大学材料科学与工程学院 上海 200240
  • 投稿日期:2012-09-27 发布日期:2012-12-10
  • 通讯作者: 赵斌
  • 基金资助:

    项目受上海市国际科技合作基金(No. 11520706100)、上海市青年科技启明星计划(B类)(No. 12QB1402800)、国家自然科学基金(No. 21071098)以及国家国际科技合作项目(No. 2011DFA50530)资助.

Research on the Phase Transition and Morphological Evolution Behaviors of Titania/Titanate Nanomaterials by Calcination Treatment

Zhao Bina, Lin Lina, Chen Chaoa, Chai Yuchaob, He Dannonga,b   

  1. a National Engineering Research Center for Nanotechnology, Shanghai 200241;
    b School of Material Science and Engineering, Shanghai JiaoTong University, Shanghai 200240
  • Received:2012-09-27 Published:2012-12-10
  • Supported by:

    Project supported by the Shanghai International Science and Technology Cooperation Project (No. 11520706100), Shanghai Rising-Star Program (B-type) (No. 12QB1402800), National Natural Science Foundation of China (No. 21071098) and International Science and Technology Cooperation Project of China (No. 2011DFA50530).

Titania/titanate nanomaterials including rutile, anatase, brookite TiO2 and sodium dititanate and trititanate were obtained by regulating the acid/alkali concentration under hydrothermal treatment. A systematical investigation was established to uncover the phase transition and morphological evolution behaviors of TiO2/titanate nanomaterials by calcining the samples including rutile TiO2 nanorods, anatase TiO2 nanocrystallines, brookite TiO2 nanoflowers, acid washed dititanate H2Ti2O5 nanosheets and trititanate H2Ti3O7 nanowires at 400, 600, 800 or 1000 ℃ for 4 h in air with the heating rate of 2 ℃/min. After heat-treatment, the products were taken out from the oven and cooled down to the room temperature. Rietveld refinements of the powder X-ray diffraction (XRD) pattern were used to generally assess the phase composition of the different samples and their crystallite sizes, and to further investigate the phase transition behavior in company with the synthetic parameters. FESEM, TEM, and HRTEM were used to characterize the morphology evolution and to further elucidate the morphological evolution of the resulting products. The crystalline phase distributed diagram of TiO2/titanate nanostructures dominated by the two experimental parameters indcluding acid/alkali concentration and calcination temperature was presented in the current work based on our experimental results, in which revealed the 5 types of phase transition and morphological evolution behaviors of titania/titanate nanomaterials. 1. Rutile nanorods → rutile nanorod aggregations → rutile micro particles. 2. Anatase nanocrystallines → anatase nanoparticle aggregations → rutile micro particles. 3. Brookite nano- flowers → brookite nanoflower clusters → rutile micro clusters. 4. Dititanate H2Ti2O5 nanosheets →anatase nanoparticle aggregations → rutile micro clusters. 5. Trititanate H2Ti3O7 nanowires → TiO2-B nanowires → anatase nanowire aggregations → rutile micro clusters. The crystal growth and phase transition mechanism was discussed based on the Ostwald’s step rule. Moreover, morphological evolution mechanism was also discussed based on the thermodynamic equilibrium regime and oriented attachment growth model.

Key words: titania, titanate, calcinations, phase transition, morphological evolution, mechanism