Doctoral Dissertations

Dongxue Zhao

Keywords and Phrases

Anatase; Battery; Hydrogen; Lithium-ion; Nano; TiO2

Abstract

"Hydrogen is a non-polluting and efficient energy carrier. One barrier to utilizing hydrogen is a reliable storage method. NaAlH4 is the prototypical example of a complex metal hydride with high hydrogen storage capacities (~ 5.5 wt.%) and acceptable reaction temperatures of around 100⁰ when using catalyst. On decomposition of these complex hydrides, such as NaAlH4, one is left with monohydride NaH. The kinetics of diffusion in the monohydrides is important because reversibility hinges on mass transport and the formation of [AlH4]- anions that must structurally coordinate with the alkali metal cation on hydrogen absorption. The NaH/NaOH system of a variety of molar ratios was investigated using in situ X-ray diffraction and differential scanning calorimetry.

Nano porous carbons (NPC) materials have mesoporous structure, large surface area (> 600 m2s/g), and high pore volume (> 0.5 cc/g). Several NPC materials for both hydrogen storage and battery applications were prepared and discussed.

Nano-sized TiO2 is a superior material for lithium-ion batteries due to its high stability, low volume change on lithiation (~ 3%), and high energy density. High purity (~ 100%) anatase TiO2 nano particles with controllable particle size from 9 to 38 nm and excellent electrochemical properties (> 220 mAh/g) were synthesized using an efficient and reliable method. The synthesis, characterization and electrochemical measurements of prepared anatase TiO2 nano particles for lithium-ion battery applications were discussed. The lithium diffusion behaviors in TiO2 and SnO2 nano particles were analyzed and compared using an extension of the galvanostatic intermittent titration technique (GITT) that utilizes the open cell potential of the relaxation portion of the GITT measurement"--Abstract, page v.

Advisor(s)

Majzoub, Eric H.
Medvedeva, Julia E.

Committee Member(s)

Hor, Yew San
Bahar, Sonya
Fraundorf, Phillip B.
Holmes, Stephen M.

Department(s)

Physics

Degree Name

Ph. D. in Physics

Publisher

Missouri University of Science and Technology

Publication Date

2015

Journal article titles appearing in thesis/dissertation

  • A study of the heat and pressure induced S105 phase in NaAlH4
  • Effects of NaOH in solid NaH: Solution/segregation phase transition and diffusion acceleration
  • Density functional theory of MH-MOH solid solubility (M=alkali) and experiments in NaH-NaOH
  • Investigation of TiO2 and other electrode materials in Lithium-ion batteries: Improving capacity and cycling performance

Pagination

xviii, 162 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2015 Dongxue Zhao, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Subject Headings

Energy storage -- DesignNanostructured materialsTitanium dioxideLithium ions

Thesis Number

T 11154

Electronic OCLC #

1003209934

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Physics Commons

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