【作者】 陈立勇；

【导师】 张祖德；

【作者基本信息】 中国科学技术大学 ， 无机化学， 2009， 博士

【摘要】 本论文旨在探索铟基Ⅲ-Ⅵ族无机半导体纳米材料的液相合成新途径。在对文献综合分析的基础上,利用有机小分子、生物小分子以及高分子添加剂等作为结构导向试剂,选择了水热、溶剂热的化学合成,实现了铟基Ⅲ-Ⅵ族半导体材料多级纳米结构的生长和组装。研究了产品的形貌、晶体结构、影响因素和形成机理等,初步探讨了材料的形貌对材料性质的影响。本论文内容归纳如下:1.通过超声辅助液相合成方法,成功合成了InOOH纳米线组装的三维结构。有机胺分子作为反应过程结构导向分子,促进了线状结构的形成。对反应溶液进行超声有利于形成均匀的纳米线结构,其原因为超声所提供的能量促使均一的InOOH晶种的形成。2.通过L-半胱氨酸生物小分子辅助,用低温水热法合成出统一形貌、直径大约400 nm花状结构β-In₂S₃纳米粉末,实验表明L-半胱氨酸分子起着两方面的作用;既提供硫源,又与In³⁺离子配位。这种结构的In₂S₃具有很大的比表面的多孔结构,在光催化器件上有潜在的应用价值。这种环境友好的生物小分子辅助液相合成方法可广泛应用在制备其它金属硫化物。3.利用两步法合成出C-In₂O₃。首先,水热法合成由纳米方块组装成的不同形貌In（OH）₃纳米材料。实验结果显示具有特殊结构的有机分子和生物分子在材料的生长和组装过程中有重要的作用,它们促进了结构基元的取向搭接,从而达到合成预期结构的目的。再通过后期热处理的方法,成功获得了具有与前驱物相似形貌的C-In₂O₃纳米粉末。这些具有特殊结构的C-In₂O₃可预期作为催化、传感器以及光电材料。4.利用溶剂热法制备出不同结构的InOOH,包括纳米棒组装的海胆状分等级结构和一维纳米结构。聚合物和有机胺分子作为capping试剂,动力学控制InOOH晶种不同晶面的生长速率,获得纳米棒状结构。热处理InOOH可制得H-In₂O₃,并继承前驱物的形貌。光降解实验结果发现样品的形貌、尺寸以及比表面对降解性能产生重要影响。更多还原

【Abstract】 The objective of this dissertation is to explore new avenue for solution-based chemical routes to prepare indium-basedⅢ-Ⅵgroup inorganic semiconductor nanomaterials.Based on a wide and in-depth literature investigation,the hydrothermal and solvothermal system were selected as the research field.Organic molecule, biological molecule and polymer additive served as structure-directing agents,a series of functional nanostructured materials including InOOH,In（OH）₃,In₂O₃ and In₂S₃ have been obtained.The morphology,crystal structure,effective condition and formation mechanism of the products have been studied.In addition,the different morphologies on their properties have also been investigated.The main points are summarized as follows:1.A ultrasonic-assisted solution route to fabricate InOOH 3D structures assembled with nanowires has been proposed.Organic amine molecules which can serve as structure-directing agent in this experiment facilitate the formation of rod-like structures.On the basis of some parallel experiments,the energy from the sonication process induced the formation of uniform seeds,which favored the formation of nanowires with uniform diameters under solvothermal condition.The synthesis technique involving several methods can be extended to the preparation of other inorganic functional materials with desired structures.2.β-In₂S₃ uniform flower-like nanostructures with the average diameter of 400 nm can be obtained via an L-cysteine-assisted hydrothermal process.The growth mechanism reveals that the combination of In³⁺ ions and L-cysteine in the reaction solution produced the complex,which served as both the indium source and the sulfur source.The porousβ-In₂S₃ with a ultra-high surface area can contribute to the potential application in building photocatalysis devices.This environmentally benign technique can widely be used to fabricate other metal sulfide nanomaterials.3.A two-step technique has been applied in the synthesis of C-In₂O₃ nanostructures. Firstly,nanostructured In（OH）₃ with different morphologies assembled by small nanocubes has been prepared via a hydrothermal process,where the intermediates show the organic molecules and the biological molecules have the influence on the growth and oriented aggregation of these building block.And then nanostructured C-In₂O₃,inheriting its precursor In（OH）₃ morphologies,has been synthesized via heat treatment.The C-In₂O₃ with special structures shows great potential in catalysis,sensor and photoelectronics.4.InOOH with different morphologies,including 1D nanostructures and urchin-like hierarchical structures assembled by nanorods,can be constructed via a solvothermal method.Organic amine and polymer additive as capping agents selectively adsorb on the crystallographic facets of the growing crystals to achieve anisotropic crystal growth kinetically.H-In₂O₃ nanocrystals have been synthesized via heat treatment InOOH,and have inherited their precursors’ morphologies. As-synthesized H-In₂O₃ exhibits excellent photocatalytic activity in the photodegradation of RhB solution under UV light irradiation,which is attributed to the special structures,size effects of nanorods and large surface area.更多还原