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摘 要：本文利用纳米氧化锌（Nano-ZnO）独特的形貌结构及其优越的物理、化学特性，运用水浴盐溶液沉淀法制备三种不同形貌的纳米氧化锌（Nano-ZnO）材料，即微球（ZnO Microballoon）、纳米薄片（ZnO Nanosheet）、纳米颗粒（ZnO Nanopartical），运用XRD、BET、SEM、TEAM等分析测试方法对材料进行表征，研究合成条件对其结构、光催化性能的影响。为了提高纳米氧化锌（Nano-ZnO）的产率，通过水浴盐溶液沉淀法将纳米氧化锌（Nano-ZnO）负载于凹凸棒土（Att）表面，制备了纳米氧化锌复合材料（Att-ZnO），从而得到一种高效、清洁、无毒、无污染的环境友好型材料。以紫外光催化降解对硝基苯胺为探针，研究所得材料的光催化性能。实验发现，纳米氧化锌（Nano-ZnO）具有良好的吸附性，三种形貌的纳米氧化锌（Nano-ZnO）材料都具有非常好的光催化性能，其中氧化锌微球（ZnO Microballoon）的光催化性能最佳，当催化剂的投料量为1.0g/L，暗吸附10min，紫外光催化反应60min，对20mg/L的对硝基苯胺的降解效率可达99.3%。另外，将纳米氧化锌（Nano-ZnO）负载在凹凸棒土（Att）上后，纳米氧化锌（Nano-ZnO）的分散性和产率明显提高，在凹凸棒土-纳米氧化锌（Att-ZnO）复合材料中，以质量比为1:5(m(Att):m(ZnO)=1:5)的Att-ZnO Microballoon和质量比为1:3(m(Att):m(ZnO)=1:3)的Att-ZnO Nanopartical的性能最好，催化剂投料量为1.0g/L，暗吸附10min，紫外光反应60min，对20mg/L的对硝基苯胺溶液的去除率均能达到95%以上；并且催化剂可以重复回收使用，重复使用的光催化降解效率也均在90%以上。该研究对于拓宽凹凸棒土（Att）应用的领域，提高纳米氧化锌（Nano-ZnO）的利用率具有重要的意义。 57235
毕业论文关键词：纳米氧化锌，水浴盐溶液沉淀，形貌，对硝基苯胺，光催化
Abstract: Because of its unique architecture and superior physical and chemical properties, zinc oxide with three different morphologies, including microballoon, nanosheet and nanopartical, was synthesized by applying constant temperature water bath salt precipitation method. XRD, BET, SEM, TEAM and other analysis methods were used to characterize structural properties of the obtained materials. Impact of synthetic conditions on their morphology characteristics and photocatalytic performance was also studied. In order to improve the yield of the zinc oxide, attapulgite (Att) was chosen as the substrate and nano-zinc oxide (Nano-ZnO) was loaded onto the surface of attapulgite by constant temperature water bath salt precipitation method to get attapulgite-nano-zinc oxide (Att-ZnO) composite materials. Photodegradation of p-nitroaniline under ultraviolet light irradiation was chosen as the model system to investigate the photocatalytic activity of the obtained Nano-ZnO and Att-ZnO. It was found that three morphologies of nano-zinc oxide all have exceptional adsorption and photocatalytic performance, especially for the nano-zinc oxide microballoon (ZnO Microballoon). When the usage amount of catalyze is 1.0g/L, photodegradation ratio of 20mg/L of p-nitroaniline reached to 99.3% within 60min. In addition, the dispersity and productivity of nano-zinc oxide have increased significantly after coaiting onto attapulgite. When the mass ratio of m(Att):m(ZnO)=1:5 and m(Att):m(ZnO)=1:3, the obtained Att-ZnO microballoon and Att-ZnO nanopartical present the excellent photocatalytic performance, respectively. With the usage amount of catalyze is 1.0g/L, the degradation rate of 20 mg/L p-nitroaniline within 60 min is more than 95%. The catalyst can be repeated and the reusable photocatalytic degradation rate is above 90%. This study has the great significance on broadening the application areas of attapulgite (Att) and improving the utilization rate of nano-zinc oxide.
Key word: Nano-zinc oxide, Constant temperature water bath salt precipitation method, Morphology, P-nitroaniline, Photocatalytic.