通过简单的湿化学反应,在酸盐和二氧化的纳米结构之间进行相位过渡
1Australian Key Centre of Microanalysis & Microscopy and School of Chemistry, The University of Sydney, NSW 2006, Australia. h.zhu@emu.usyd.edu.au
Journal of the American Chemical Society
|May 5, 2005
概括
泰坦酸纳米纤维通过湿化学过程经历可逆相过渡到二氧化 (TiO2) 多态. 这些转换在适度温度下很容易发生,使得纳米结构的工程成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 化学工程是化学工程的重要组成部分.
背景情况:
- 泰坦酸纳米纤维具有独特的尺寸和形态特性,与耐火矿物质有很大不同.
- 这些纳米结构具有很高的表面与体积比,这有助于它们显著的反应性.
- 现有的生产TiO2多态体的方法通常需要高温或恶劣的条件.
研究的目的:
- 在温和条件下研究酸盐纳米结构的相位过渡到TiO2多态.
- 探索这些转变的可逆性和新型纳米结构的合成.
- 通过水力金反应来证明商业应用的潜力.
主要方法:
- 使用无机化合物合成酸纳米纤维的热水反应.
- 在酸性水溶中进行湿化学处理,以诱导向TiO2多态 (anatase和rutile) 的相过渡.
- 使用缩NaOH溶液进行反应,将TiO2纳米晶体转化回酸纳米管.
主要成果:
- 泰坦酸纳米结构通过周围环境温度附近的湿化学过程轻易转化为TiO2多态 (anatase和rutile).
- 较低的热水合成温度产生酸纤维,由于缺陷和表面积增加,在较低的温度下转化为TiO2.
- 在酸盐和TiO2多态体之间实现了可逆转换,从TiO2纳米晶体产生空心酸盐纳米管.
- 通过水电金学,成功地将酸盐和TiO2纳米结构直接从鲁矿物和工业级鲁中合成.
结论:
- 泰坦酸盐和TiO2多态体之间的可逆相变通路通过在中等温度下的湿化学反应存在.
- 这些工程过渡允许在可访问的条件下控制生产各种纳米结构.
- 从矿物来源的水电金合成证明了生产酸盐和TiO2纳米结构的商业可行性.
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