项链型钯金异质纳米材料的可控合成及其催化性能研究

发布时间：2018-03-01 16:19

本文关键词： 贵金属纳米材料可控合成催化异质结构甲基橙亚甲基蓝　出处：《华中农业大学》2017年硕士论文　论文类型：学位论文

【摘要】：贵金属纳米材料在催化反应、生物传感等诸多领域有着极大的应用空间和发展潜力,因其性质与形貌结构有着紧密关联,可控的合成具有特殊结构的贵金属纳米材料具有重要意义。异质纳米结构的优越性能,使其最近受到了广泛的关注。本论文主要可控合成了由超细超长的Pd纳米线串联多个Au纳米颗粒形成的项链型钯金异质纳米材料,并对其性质与形貌之间的关系进行了研究,主要研究结果如下:1.使用超细超长碲纳米线作为模板,CTAB作为表面活性剂、PdCl2及HAu Cl4作为前体,通过精确的调控还原剂的用量,可以对项链型钯金异质纳米材料上的Au纳米颗粒的间距和尺寸进行调控。当调节金前体用量时,Au纳米颗粒的尺寸可被进一步调控。通过TEM、HRTEM、HAADF-STEM、XRD等技术对合成的材料进行多种表征,得到了在金前体用量固定时,还原剂用量和Au纳米颗粒的间距和尺寸的量化关系,即随着还原剂用量的增加,金纳米颗粒的间距和尺寸下降,金前体的用量改变则会引起金纳米颗粒尺寸的改变,并且对项链型钯金异质纳米材料的形成过程进行了讨论,给出了合理解释。2.将项链型钯金异质纳米材料用于甲基橙、亚甲基蓝或对硝基苯酚的降解,对其催化活性进行研究。首先测试了具有不同Au纳米颗粒间距和尺寸的异质纳米项链的催化性质,然后将其与Pd Au纳米线、Pd纳米线、Au纳米颗粒以及Pd纳米线和Au纳米颗粒的混合物等进行对照。结果显示项链型钯金异质纳米材料的催化活性及催化稳定性均具有优于对照组,而且项链型钯金异质纳米材料的活性随着结构改变表现出了一定的变化规律:当Au纳米颗粒的间距和尺寸在一定范围内变大时,材料表现出了更好的催化活性。
[Abstract]:Noble metal nanomaterials have great application space and development potential in many fields such as catalytic reaction, biosensor and so on, because their properties are closely related to their morphology and structure. The controllable synthesis of noble metal nanomaterials with special structures is of great significance. In this thesis, the necklace-type palladium and gold heterogeneous nanomaterials formed by ultrafine and ultra-long PD nanowires in series with several au nanoparticles have been synthesized, and the relationship between their properties and morphology has been studied. The main results are as follows: 1. Using ultrafine ultra-long tellurium nanowires as templates, CTAB as surfactants PdCl2 and HAu Cl4 as precursors, the amount of reductant can be accurately controlled. The spacing and size of au nanoparticles on the necklace type palladium gold heterogeneous nanomaterials can be controlled. The size of au nanoparticles can be further regulated when the amount of gold precursor is adjusted. The synthesized materials are characterized by TEMU HRTEMU HAADF-STEMXRD and other techniques. The quantitative relationship between the amount of reducing agent and the spacing and size of au nanoparticles is obtained when the amount of gold precursor is fixed, that is, with the increase of the amount of reducing agent, the spacing and size of gold nanoparticles decrease. The change of the amount of gold precursor will lead to the change of the size of gold nanoparticles, and the formation process of the necklace type palladium and gold heterogeneous nanomaterials is discussed, and the reasonable explanation is given. 2. The necklace-type palladium and gold heterogeneous nanomaterials are used in methyl orange. The catalytic activity of methylene blue or p-nitrophenol was studied. Firstly, the catalytic properties of heterogeneous nano-necklace with different au nanocrystalline spacing and size were tested. Then compared with PD au nanowires and PD nanowires and the mixture of PD nanowires and au nanoparticles, the results showed that the catalytic activity and catalytic stability of the necklace type palladium gold heterogeneous nanomaterials were superior to those of the control group. Moreover, the activity of the nanocrystalline palladium and gold heterostructure changed with the change of structure. When the spacing and size of au nanoparticles increased in a certain range, the catalyst showed better catalytic activity.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;TB383.1

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