Dissertation > Excellent graduate degree dissertation topics show

Preparation and Characterization of Nanosemiconductor Materials with Ordered Stuctures

Author: ZhangZhiYan
Tutor: ZhuHaiTao
School: Qingdao University of Science and Technology
Course: Inorganic Chemistry
Keywords: ordered nanostuctures TiO2 Bi2WO6 NiO hollow micro-spheres
CLC: TB383.1
Type: Master's thesis
Year: 2009
Downloads: 135
Quote: 0
Read: Download Dissertation

Abstract


Nanosemiconductor materials with unique quantum size effect, surface effect,macroscopical quantum tunnel effect, have potential applications in many fields, suchas photoelectric converting devices, catalysis, sensors, and optical devices, etc. Basedon these typical performance, ordered nanomaterials with better or newer propertieshave attracted increasing extensive attention to prepare a variety of ordered nanomaterials.Several nnaomaterials with ordered sturcurte were prepared and characterizedin this paper.In this thesis, TiO2, Bi2WO6 and Ni(OH)2 ordered nanostuctures constructed withnanoparticles were successfully prepared through facile hydrothermal approach. ByTEM, SEM, XRD and UV-Vis spectrometer, the influence of fabrication conditionson the structure and morphology of ordered nanostuctures were characterized. Thesynthesis mechanism and assembly factors were also studied.The results and conclusions are as followed:1) ordered mesoporuous nanospheres composed of nanoparticles were synthesizedby titanium sulfate modified with polyvinylpyrrolidone(PVP) through solvent-thermal method. Its forming mechanism was explored.2) The size of TiO2 is 50-70 nm, by adjusting the concentration of titanium sulfatecould attain more ordered nanosperes with mesoporous morphologies. More dispersedspherical particles were obtained by adjusting the amount of PVP. Bychanging reaction time, nanosperes with more uniform size could be synthesized.3) PVP could influence the products seperation and morphology. It apparently improvedsamples’size control so that size almost retained unchanged compared withsamples before calcination. Furthermore, PVP was burnt in the process of calcination,which made PVP transform to C and doped into TiO2 products.4) Bi2WO6 with ordered flowerlike stucture assemblied by nanosheets have been synthesized.The experimental results indicated the products’better catalytic propertywithin visible-light region. In many factors, hydrothermal temperature could affect the morphologies obviously.5) Without surfactant, Ni(OH)2 nanosheets have been prepared through hydrothermalmethod. Experimental conditions were studied, results indicated that thinnerNi(OH)2 nanosheets could be obtained at 150℃, followed degradation of methylorange testified the sample’s better catalytic property. After calcination, resultedNiO products’catalytic performance were improved compared to Ni(OH)2nanosheets.6) ordered stuctures assemblied by Ni(OH)2 nanosheets were attained with hollowglass micro-spheres as template. After calcination Ni(OH)2 hollow micro-spherescould be transformed NiO. The assembly factors were studied.Creative points:1) A series of ordered stuctures assemblied by nano-constructional-unit structureshave been synthesized though facile hydrothermal(or. solvent-thermal) method. Inthis paper, ordered mesoporous TiO2 nanospheres, Bi2WO6 with ordered flowerlikestucture, NiOnanosheets have been obtained respectively.2) Ni(OH)2 hollow micro-spheres with uniform coated-layer were prepared throughlayer-by-layer method. Calcination made Ni(OH)2 transformed to NiO hollow microspheres.

Related Dissertations

  1. Studies on the Synthesis and Technology of Dipentaerythritol and Its Derivative,TQ223.164
  2. Preparation of Based on the Phenolic Resin of Activated Carbon and Adsorption-Photopcatalytical Character of Supported TiO2,TQ424.19
  3. The Preparation and Research of Magnetically Separable TiO2 Photocatalyst Nanofibers,TB383.1
  4. The Study of Preparation and Photocatalytic Activity of TiO2 by Electrospinning,O614.411
  5. Of Bi N Co-doped TiO \u003csub\u003e 2 \u003c/ sub\u003e of the preparation and performance,O614.411
  6. Investigation of Fabrication, Characterization and Property of Fuctional Titanium Dioxide Nanoporous Materials,TB383.1
  7. Investigation of Preparation and Properties of Ordered Porous TiO2,TB383.2
  8. Preparation and Performance of V2O5-WO3/MOx/Cordierite Catalyst Modified with Cu、Mn、Ce for DeNOx,X701
  9. Study on Properties of Ce、Co、Ni/V-W/TiO2 Modified by Composite Sol for Selective Catalytic Reduction,X701
  10. Preparation of One-dimensional Nano TiO2 and Study on the Decolorization of Dyeing Wastewater,TB383.1
  11. Bio-inspired Mineralization Process of TiO2 and CaCO3 in Agarose Gel Medium,O611.3
  12. Study the Detection and Adsorption of Formaldehyde in Indoor Air,X831
  13. Inorganic filler of the modified polylactic acid,TQ320.1
  14. Copper oxide porous hollow microspheres Preparation and Characterization,O614.121
  15. Ni / TiO 2 -SiO 2 Preparation, Characterization and Hydrogenation of Maleic Anhydride,TQ225.2
  16. Nano LaFeO 3 Controllable Synthesis and TiO 2 bridged construct composite photocatalyst,O643.36
  17. Core-shell polymer microspheres synthesis, modification and application,O631.3
  18. Doped Modification and Application of Titania Photocatalyst,O643.36
  19. Hydrogen Evolution Process of Water Electrolysis Assisted by TiO2 Nanotubes and TiO2/ZnO Nanorodes Assembled on Ni Substrate,TQ116.21
  20. Nano- TiO 2 Photocatalytic Preparation and characterization of composite films,TB383.2
  21. Morphology-controlled Synthesis of Bi2S3-based Photocatalysts and Their Photocatalytic Performance,TB383.1

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