Dissertation > Excellent graduate degree dissertation topics show

Hydrothermal Synthesis of LiNbO3 Nanopowders and Dielectric Properties of Their Sinters

Author: ChengShiZuo
Tutor: ChenZhenNing
School: Harbin Institute of Technology
Course: Industrial Catalysis
Keywords: lithium niobate nanopowders hydrothermal synthesis method doped ceramics dielectric properties
CLC: TQ174.7
Type: Master's thesis
Year: 2006
Downloads: 247
Quote: 0
Read: Download Dissertation


As the competition of lead-free piezoelectric ceramics in investigation and exploiture increasingly vehement, the excellent properties of LiNbO3 ceramics are far-ranging cared by scholars in many countries. It is difficult to gain densification, integrality and good capability LiNbO3 ceramics by traditional solid-state reaction and agglomeration method. In recent years, for making ceramics powder with symmetrical component and small grain size, wet chemistry methods are developing quickly. Especially, the ceramics powder made by hydrothermal synthesis does not need high temperature calcinations, so it avoids grain growth, defect-forming and impurity introduction. For these reasons, the powder has high sintering activity.In the thesis, LiNbO3 nanoparticles were hydrothermally synthesized at 240℃for 12h using Li2CO3 and Nb2O5 as starting materials by carefully controlling conditions in the first place. The influences of several factors such as: starting materials, temperature and reaction time on resultant products were investigated in the hydrothermal process by means of X-ray diffraction (XRD), infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The powder under optimal conditions was characterized by thermal analysis (TG-DTA), transmission electron microscopy (TEM) and X-ray fluorescence (XRF).The crystals reported in this condition have perfect crystal morphologies. TEM and X-ray powder diffraction data show consistent with the crystallite size of 50nm. Stoichiometry is obtained by hydrothermal method while the Curie temperature is 1180℃.In the next place, Fe-doped and Ce-doped LiNbO3 nanoparticles ceramics powders were synthesized by hydrothermal method in the determined conditions respectively. The effect of ion-doped on lattice structure, chemical elements, ultraviolet spectrophotometry and crystal appearance characteristics of the powders was analyzed. The results indicated that: when ion-doped quantity was not more than 0.1%, there was no obviously transformation in the lattice structure; the ratio of Nb and Li which transformed to mol was less than 1:1 in the Fe-doped (0.1%) LiNbO3; there were no notably change about ultraviolet

Related Dissertations

  1. The Preparation and Thermoelectric Properties of Rare Earth Subsituted Ag Composite Ca3Co4O9-Based Oxides,TQ174.1
  2. Studies on Synthesis, Characterization and Properties of Fe-V Co-doped TiO2 Catalyst,O614.411
  3. Fabricationand Properties of SiC-AlN Multiphase Ceramics Prepared by Gelcasting,TQ174.62
  4. Flexible,rigid,Synthesis and characterization of mixed ligand complexes,O621.1
  5. Of Bi N Co-doped TiO \u003csub\u003e 2 \u003c/ sub\u003e of the preparation and performance,O614.411
  6. Gel - Foam Preparation of porous alumina insulation materials,TQ174.1
  7. Investigation of Fabrication, Characterization and Property of Fuctional Titanium Dioxide Nanoporous Materials,TB383.1
  8. Investigation of Preparation and Properties of Ordered Porous TiO2,TB383.2
  9. Iron-doped SnO \u003csub\u003e 2 \u003c/ sub\u003e ceramics and thin films research,TQ174.6
  10. Study on the Thermal Insulation Porous Ceramics,TQ174.1
  11. Preparation and Luminous Property of Tm and Dy Doped YSZ Coating,TG174.442
  12. Based on the study of all-optical logic gates for fiber nonlinear effects,TN253
  13. Preparation and Properties of Filtering Ceramics for High Temperature Exhaust Gas,TQ174.6
  14. Preparation and Properties of Non-hydrogenated Diomand-like Carbon and Non-hydrogenated Si-doped Diomand-like Carbon Films,TB383.2
  15. Research on Luminescence of Nanoporous Glass Composite Materials,TB383.1
  16. Study on Low Temperature Sintered PSN-PZT Piezoelectric Ceramics,TM282
  17. The Characterization and Polymerization Shrinkage Properties of Dental Composite Resins with Fluorphlogopite/Fluorapatite Fillers,R783
  18. The Study of Glass Ceramics-Ceramics Composite Bora’s Stress,TB301
  19. Study on Two Dimensional Ultrasonic Vibration Grinding Temperature Field Distribution Character of Nano ZrO2 Ceramics,TG580.6
  20. Microstructures and Properties of Brazing Joint of Al2O3 Ceramic and Q235 Steel,TG407
  21. Study on Uniformity and Tribological Behavior of DLC Film on Surface of Ceramics,TG174.453

CLC: > Industrial Technology > Chemical Industry > Silicate > Ceramic Industry > Ceramics
© 2012 www.DissertationTopic.Net  Mobile