Dissertation > Excellent graduate degree dissertation topics show

The Controlled Synthesis of Noble Metal Nanoparticles and Their Properties in Optic and Catalytic Field

Author: GongXueZhong
Tutor: HuangShaoMing；YangYun
School: Wenzhou University
Course: Physical and chemical
Keywords: noble metal nanoparticles seeding-growth controlled synthesis electrochemical oxidation
CLC: TB383.1
Type: Master's thesis
Year: 2011
Downloads: 131
Quote: 0
Read: Download Dissertation

Abstract


Noble metal nanoparticles have potential applications in many fields, such as catalysis, biosystem, energy and environment. The properties and applications of noble metal nanoparticles have strong dependence on their structure, shape and size. Therefore, the controlled synthesis of noble metal nanoparticles has been extensively pursued. In this dissertation, based on seeding-growth, noble metal nanoparticles with various shapes, structures and sizes were synthesized and new mechanism was proposed. Furthermore, their optic and catalytic properties were studied. The main research work is listed as following:（1） Through using seeding-growth and galvanic reaction, hollow AuAg@Au nanoparticles with alloy core （HNACs） have been prepared. Through adjusting the core size, the amount of HAuCl4, and the diameter of Au@Ag, the fabrications of various HNACs were achieved. Also a new galvanic reaction process was proposed based on careful observation. By using 2-Naphthalenethiol as a probe molecule to investigate their SERS activity and the results demonstrated their good performance.（2） The Pt nanoparticles （NPs） with controlled shape and size were synthesized by using seeding-growth. By adjusting the reactive conditions, such as the molar ratio of Pt metals from Pt（acac）2 and seed, the seed diameter, the NPs growth could be controlled to give variously shaped NPs. A reasonable mechanism in which the NP shape is c/s-dependent （c=concentration of precursor, s=total surface area of NPs） was figured out to explain shape evolution process successfully. The prepared Pt NPs were further tested for catalytic oxidization of methanol and results demonstrated that their shapes have great impact on catalytic properties, and the branched Pt nanoparticles showed the greatest catalytic performance.（3） By using the oxide nanoparticles （Mn3O4） as catalyst and modifying reactive conditions, rarely-observed polycrystalline twinned Pt nanoparticles （NPs） and single crystalline nanorod could be synthesized. A possible mechanism was proposed that the Mn3O4 nanoparticles were not consisted in the Pt nanoparticles, instead just as a catalyst or a modifier of catalyst contributing to the form of Pt polycatalline or rod-like nanoparticles. In addition, high index facets with high density were observed on the edge of Pt nanorod, which can improve the catalytic performance in the electroxidation of methanol. Besides, such nanostructure can be further developed to be more applicable nanocatalysts with high efficiency.

Related Dissertations

  1. The Synthesis and Catalytic Properties Characterization of 0-Dimension and 1-Dimension Noble Metal and Alloy Nanomaterials,TB383.1
  2. Preparation and characterization of bismuth oxide nanoparticles Analytical Chemistry,TB383.1
  3. Design, Synthesis and Applications of Noble Metal Nanoparticles/1-dimensional Structure Nanocomposites,TB383.1
  4. Research on Phytoremediation of Petroleum-Contaminated Soil by Field Crops,X53
  5. Synthesis and Properties of ZnO Rods and Lotus Leaves-shaped Nanostructures by Solution Approach,TB383.1
  6. Separation, Superficial Coating and Properties Research of Noble Metal Nanoparticles,TB383.1
  7. The Morphology and Crystal Phase Controlled Synthesis and Separation of CdS Nanorods,O614.242
  8. Synthesis of Noble Metal Nanoparticles and Sensing Analysis Application,TB383.1
  9. Single Nanoparticle Counting Technique and Its Application on Thrombin Assay,Q55
  10. First Principles Study of Catalytic Reaction Mechanism on Noble Metal Surface and Nanoparticle,O469
  11. Gold nanorods in Au (111) surface and the STM -induced luminescence dispersed Discussion,TB383.1
  12. Synthesis the Mono-dispersed Noble Nanoparticles and the Study of Optical Properties,TB383.1
  13. Localized Surface Plasmon Resonance Properties of Noble Metal Nanoparticles,TB383.1
  14. Effect of Different Materials Priming on Seed Germination and Seedlings’ Physiological Characteristics of Watermelon Seed,S651
  15. Preparation and Application of Electrochemical Biosensors Based on Carbon Nanotubes,O657.1
  16. The Effects of Different Light and Temperature on the Growth and Physiology Characteristics of Muskmelon Seedling,S652
  17. Investigation on the Fabrication of Dissolved Oxygen Sensors Based on Carbon Materials,X85
  18. Studies of Thymus Serpyllum L. Var.asiaticus Kitag. Allelopathy on Weeds,S451
  19. Influence Mechanism of Noble Metal Nanoparticles on the Fluorescence of Quantum Dots and Porphyrins,TB383.1
  20. Fabrication of Conducting Polymer/Precious Metal Composite Materials and Their Application in Small Organic Molecules Electrocatalytic Oxidation,TB33
  21. Preparation of Noble Metal Nanoparticles Composite Glass and Research of Photoelectric Properties,TB383.1

CLC: > Industrial Technology > General industrial technology > Materials science and engineering > Special structural materials
© 2012 www.DissertationTopic.Net  Mobile