【作者】 刘一；

【导师】 胡正水；

【作者基本信息】 青岛科技大学 ， 材料物理与化学， 2010， 硕士

【摘要】 水热法有可能实现在常规条件下不能进行的反应,在合成纳米材料方面具有颗粒小、均匀、无团聚、纯度高、晶型好、形状可控等特点并且在制备薄膜方面有广泛应用。本文用水热法合成了纳米氧化锆和氧化铝,研究了饱和CO₂体系在制备纳米氧化锆空心球方面的应用和pH值对γ-AlOOH形貌的影响。并对球形γ-AlOOH做了电化学方面的应用;利用水热法在钢铁表面上生成了一层水热晶化膜,提出了高温高压下的水热合成晶化膜保护机理,并对成膜后的铁片进行了电化学测试和盐水完全浸泡实验,讨论了样品的耐腐蚀性能。主要结果如下:（1）在雪碧中的饱和CO₂体系中制备纳米氧化锆时,雪碧中的蔗糖在水热环境中变为炭,严重影响了CO₂的气模作用。为了消除雪碧中其他成分尤其是蔗糖对实验结果的影响,采用NH4HCO3的水溶液来提供饱和CO₂的反应环境,最终在此反应体系中得到了空心纳米球结构,但团聚严重。讨论了不同反应溶剂和表面活性剂对样品形貌的影响,结果表明:在以NH4HCO3为产生CO₂源的条件下,只有在水介质中才可以得到空心结构的氧化锆,在这个过程中,水溶的CO₂微气泡的模板作用是主要的,而表面活性剂仅在水溶液中才起到一定的的模板作用。（2）对加入SUDEI作表面活性剂合成的空心结构γ-AlOOH进行了电化学测试。结果表明,SUDEI在水热过程中与γ-AlOOH产生了化学吸附的表面修饰,为Hb提供一个具有生物相容性的界面,促进了Hb在电极表面的直接电化学行为,加快了Hb的电子转移速率。用氢氧化钠调节反应介质的pH值,结果表明,pH值是影响γ-AlOOH形貌的重要因素。用AMP-95做反应溶剂,反应12h后得到了比较罕见的γ-AlOOH三次组装体。（3）通过水热结晶的方法在钢铁表面水热合成了一层黑色晶化膜,提出了在高温高压下的水热合成晶化膜保护机理,探讨了不同反应条件对成膜的影响,并对处理后的样品进行了电化学测试和耐腐蚀实验,结果表明,在300℃下水热反应12h是最佳的水热条件,延长反应时间和提高反应温度不利于晶化膜的生成,样品的电化学极化曲线测试表明经盐酸处理的铁片在300℃下水热反应12h后样品对腐蚀介质和O₂向金属表面扩散的阻碍作用更大。更多还原

【Abstract】 Hydrothermal process has the possibility to achieve some reactions which may not be carried out in conventional condition. In the preparation of nanomaterials, hydrothermal process has the advantages of small particles, uniform, non-agglomeration, high purity, well crystallized and morphology controllable. Recently, application of hydrothermal process in preparation of film has attracted much attention. In this paper, zirconia andγ-AlOOH were synthesized by hydrothermal process. Application of saturated CO₂ system in the preparation of zirconia hollow spheres and influence of pH on the morphology ofγ-AlOOH ware discussed. And the application ofγ-AlOOH sphere in electrochemistry was researched. Crystallization membrane on iron was synthesized by hydrothermal process and the protection mechanism was proposed. Electrochemistry and saline soak test were carried out. The anti-corrosive performance of samples was discussed on this basis. The main results are concluded as follows:（1） Sucrose transforms to carbon that has a seriously affect on the formation of zirconia hollow spheres when the reaction carried out. In order to eliminate the affect of sucrose, NH4HCO3 solution was used to provide the environment of saturated CO₂ system. Zirconia hollow structure was finally prepared in this reaction system. The effects of reaction solvent and surfactant on the morphology of samples were discussed. The results indicated that hollow structured zirconia was only obtained when water as reaction medium. In this process, CO₂ plays an important role in the formation of hollow structure, and the effect of surfactant is secondary.（2） Hollow structuredγ-AlOOH was synthesized with urea as precipiting agent. The electrochemistry application ofγ-AlOOH was discussed. The result indicates that SUDEI has a chemical adsorption withγ-AlOOH. And SUDEI provides a biological compatible contact surface which promotes the electron transfer process of Hb. The pH was adjusted by NaOH solution. The result indicates that the pH plays a key role in the formation of morphology ofγ-AlOOH. Three assembly ofγ-AlOOH was prepared in AMP-95 after reacted for12h.（3） Crystallization membrane on iron was synthesized by a hydrothermal process. On this base, a crystallization membrane protection mechanism was proposed. The influence of different reaction conditions on crystallization membrane was discussed. The results of the electrochemistry and saline soak test indicate that the optimal reaction condition is to react 12h under 300℃. The extension reaction time and the enhancement reaction temperature does not favor to production of the crystallization membrane. Electrochemistry application of the samples shows that the iron treated by the optimal reaction condition has a larger hindering effect on corrosive medium and O₂.更多还原