温度对钛酸盐纳米管水热转化的TiO_2纳米晶形貌演变的影响机制  

Effect of Temperature on Morphology Evolution of TiO_2 Nanocrystals Prepared by Hydrothermal Treatment of Titanate Nanotubes and Transformation Mechanism

作　　者：方晓明[1] 周美玲[1] 许元妹[1] 熊剑[1] 张正国[1] 

机构地区：[1]华南理工大学化学与化工学院,传热强化与过程节能教育部重点实验室,广州510640

出　　处：《人工晶体学报》2010年第B06期64-68,72,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(No.20573038);教育部新世纪优秀人才支持计划(NCET-07-0312)

摘　　要：钛酸纳米管水热转化是制备晶相组成和形貌可调控TiO2纳米晶的工艺易控及成本低且收率高的途径。本文研究了两种pH值体系中,水热处理温度对钛酸纳米管水热转化的TiO2纳米晶形貌演变的影响。当钛酸悬浮液的pH值为2.0时,钛酸纳米管水热转化为锐钛矿相纳米晶,且随着水热温度的升高,纳米晶的形貌向规则的双锥形演变;对于pH为0.5的强酸性体系,钛酸纳米管水热转化为金红石相纳米棒,并随着水热温度的升高,其形貌向带有两锥形尖端的长方体纳米棒演变。最后,结合TEM和HRTEM分析,探讨了钛酸纳米管向不同晶相组成和形貌的TiO2纳米晶的水热转化及其形貌演变机制。Hydrothermal treatment of titanate nanotubes is a manageable process with high yield and low cost for preparing TiO2 nanocrystals with controllable phase composition and morphology. In this paper, the effect of temperature on the morphology evolution of TiO2 nanocrystals prepared by hydrothermal transformation from titanate nanotubes were studied. When the pH value of titanate nanotube suspension was 2.0, the titanate nanotubes transformed into anatase nanocrystals and their morphology evolved into bipyramid with increasing hydrothermal temperature. When the pH value of titanate nanotube suspension was 0.5, the titanate nanotubes transformed to ruffle nanorods and their morphology evolved into cuboid nanorods with two pyramidal ends with increasing hydrothermal temperature. Finally, the mechanism for formation and morphology evolution of the TiO2 nanocrystals on the basis of TEM and HRTEM images was discussed.

关 键 词：TIO2纳米晶 水热法 钛酸盐纳米管 形貌演变 

分 类 号：O614.411[理学—无机化学]