钛金属表面结构可控多层钛酸盐纳米管薄膜的制备和结构稳定性

Structure-tunable Synthesis and Structural Stabilities of the Multilayered Titanate Nanotube Thin Films Grown on Titanium Metal Surface

在水热条件下,通过控制反应温度和氢氧化钠的浓度,在钛金属表面得到结构可控的多层钛酸盐纳米管薄膜.根据扫描电子显微镜和高倍透射电子显微镜的观测结果,认为钛金属表面多层钛酸盐纳米管薄膜的形成经历以下4个阶段:(1)钛金属的水合和碱性钛酸盐水凝胶的生成;(2)碱性钛酸盐水凝胶分解并形成层状Na2Ti3O7;(3)层状Na2Ti3O7的生长;(4)层状Na2Ti3O7的劈裂和多层卷曲成轴形成纳米管.研究了薄膜形成后机械处理对薄膜形貌和结构稳定性的影响,并利用超声的方法实现了多层膜的层分离.

Multilayered titanate nanotube thin films were grown on titanium metal surface via a hydrothermal surface treatment process.A general formation mechanism for oriented titanate nanotube thin film was proposed on the basis of detailed SEM and TEM observation of the products.The overall formation of titanate nanotube can be summarized as a sequence of four steps：（1） titanium dissolution and alkali titanate hydrogel formation;（2） alkali titanate hydrogel dissolution and layered Na2Ti3O7 formation;（3） layered Na2Ti3O7 growth;（4） nanotube formation via Na2Ti3O7 splitting and the multilayer scrolling process.The effects of post-treatment conditions on the film morphology and stability were examined.The layer-delaminating of multilayered titanate nanotube thin films were obtained after ultrasonic treatment.