【作者】 赵云龙；

【导师】 卢红霞；

【作者基本信息】 郑州大学 ， 材料学， 2011， 硕士

【摘要】 氧化锌具有优异的光催化、光电、气敏、压电等性能,同时作为半导体材料又有成本低廉、无毒、制备简单等优点,因此一直被认为是解决目前能源、环境等问题的战略材料之一。本文在以前研究的基础上采用低温溶液体系制备了纳米氧化锌及氧化锌／氧化铟复合材料,研究了低温条件下氧化锌及其复合材料制备的影响因素,并在此基础上探讨了其形成机理,最终实现对其形貌的可控制备,同时对其性能进行了研究。此种方法具有工艺简单、对设备要求低、可重复、可规模化制备等优点。主要结论如下：以醋酸锌、氨水、六亚甲基四胺等为原料,在低温水溶液体系内研究了不同因素对氧化锌的影响,并对其生长机理进行了研究。1)在水浴条件下研究了温度对产物的影响,结果表明当温度低于40℃时,制备产物为氢氧化锌,当温度高于这一临界值时产物为氧化锌。2)研究发现添加剂的添加对氧化锌形貌有着重要的影响。当无添加剂时,生成的是1μm左右的氧化锌微米棒,尺寸不均一且出现团聚。当添加添加剂时发现氧化锌形貌变为纺锤状,尺寸为100nm左右,均一且没有团聚。这主要是由于添加剂的限制和诱导作用引起的。3)针对低温溶液法制备的氧化锌做了光致发光性能测试,结果显示低温制备的氧化锌主要包括有三个发光区域：紫外区(380-400nm)、蓝光区(460-480nm)、黄光区(540-580nm),同时本论文对其发光原理进行了阐述。4)研究发现这种纺锤状氧化锌对一氧化氮具有很好的气敏性和选择性在低温溶液法制备纳米氧化锌的基础上,本文采用原位合成法制备氧化锌／氧化铟微纳米复合结构。研究表明原位合成法制备的氧化锌／氧化钢复合材料为纺锤状氧化锌表面包裹颗粒状纳米In203的微纳米复合结构,In203颗粒尺寸均一、没有团聚。在对复合材料光致发光性能的研究中,我们发现In203的掺杂对复合材料的光致发光性能有很大影响,其中紫外峰出现50nm的红移并且强度降低,蓝光区相对强度增强,同时黄光发射区基本消失,分析可知这些现象主要是由于铟元素的掺入和热处理引起的。此外,氧化铟复合在很大程度上提高了氧化锌的气敏性能。本文尝试采用溶液法制备氧化锌及其复合薄膜。这种片状薄膜均一性好、没有团聚,具有很高的比表面积和介孔结构,是一种很好的支撑材料和功能材料。此方法工艺简单、成本低廉,是一种适合工业化生产的制备工艺。更多还原

【Abstract】 Zinc oxides have been considered as important materials to resolve the energy and environmental issues, because of their excellent optical, gas sensing, photocatalysis, piezoelectric and other properties. At the same time, Zinc oxides have more advantages compared with other materials, such as non-toxic, low-cost, and simple preparation. In this paper, ZnO and ZnO/In2O3 composite materials have been successful prepared by a solution method at low temperature on the basis of previous studies. We studied the factors on the preparation, and discussed its formation mechanism. This method has many advantages, such as the simple process, low equipment requirements, repeatable, large-scale preparation. Finally, the properties of zinc oxide and its composites were characterized and the results showed that the samples obtained have very excellent optical and gas sensing performances. This method is a very promising technology for zinc oxide and its composites. The main conclusions are as follows:First, we studied the influence of different factors on the morphology of zinc oxides prepared from zinc acetate dihydrate, ammonia and hexamethylenetetramine in aqueous solution at low temperature. 1) The products have changed with the increase of temperature. Zinc hydroxides have been prepared when the temperature was below 40℃. On the contrary, the product was zinc oxides when the temperature was higher than the critical value (40℃).2) The study has found that the addition of additives has an important influence on the morphology of zinc oxides. The products were heterogeneous in size and had reunion when not adding hexamethylenetetramine. While spindle-shaped zinc oxide nanostructures with an almost uniform size of 100nm in diameter and 100-200nm in length were obtained with adding additives. This was mainly due to limitations and induction on morphology of additives.3) Photoluminescence spectra (PL) of zinc oxides prepared at low temperature were studied. The results showed that zinc oxides prepared at low temperature including three light emitting regions:the ultraviolet region (380-400nm), blue zone (460-480nm), yellow zone (540-580nm), and its light-emitting principles were described in this paper. 4) Spindle-shaped zinc oxide nanostructures sensors appeared the advantage of high selectivity for Nitric oxide.Micro/nanostructured ZnO/In2O3 composites have been prepared in situ growth at the low-temperature basic on our previous study. Results showed that the hierarchically micro/nanostructures ZnO/In2O3 composites with spindle-shaped zinc oxide particles with 100-200nm in diameter and about 500nm in length and indium oxide particles with 20-50nm in diameter. The size of zinc oxide and indium oxide were uniform and unagglomerate, indium oxide particles uniformly distribute on the surface of zinc oxide particle. Comparing with the morphology of composites without additives, we found that the addition of additives has great influence on the morphology and composite state of indium oxide of composite materials. In the photoluminescence (PL) properties of composite materials research, we found that the doping of indium oxide has great influence on the photoluminescence of composite material, which a red shift (about 50nm) and lower intensity appeared at UV peak, the relative increasing intensity at blue area, in addition to, yellow luminescence zone disappeared. The results show that these phenomena mainly due to the incorporation of indium elements and heat treatment. The sensing property of Zinc oxide has a great advantage because of dipping of indium oxide.We try to prepare the zinc oxide and composite films at solution. The results showed that the homogeneity of sheet film is good:no reunion with high surface area and pore structure be good as support materials and functional materials. This method is a simple, low cost preparation process for industrial production.更多还原