On the phase transition and photo-reactivity on the micro-sized titanium dioxide single crystal.

Titanium Dioxide (TiO2) has been extensively studied across various fields including photocatalysis, electrochemistry, optics, etc. Studying the micro-sized TiO2 single crystals could bridge the gap between the nano-sized crystal TiO2 results and theoretical studies on their bulk crystals and design the TiO2-based high-reactivity photocatalysts. This thesis, anatase TiO2 microcrystals are used to study the anatase-to-rutile phase transition (ART) process mechanism and compare the photo-reactivity to the bulk single crystals. Scanning Electron Microscopy (SEM), Raman Microscopy, and Photoluminescence (PL) Microscopy are used for characterization. The ART study shows the transition is surface-initiated and mainly surface-controlled with two distinct transition pathways observed. The phase concentration calculated from Raman spectra indicates a first-order reaction mechanism. Our study on reactivity reveals a two-stage reaction process via time-evolving concentration calculated from PL spectra. Kinetic model fittings show that each microcrystal has a different reaction rate for complex reasons like defects and charge recombination rate.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Masters

Grantor

Baylor University.

Year dc:date.issued

2024

Author dc:creator

• Zhu, Hao, 1995-

Advisor dc:contributor.advisor

• Zhang, Zhenrong.

• Titanium dioxide.
• Phase transition.
• Photoreaction.
• Microcrystal.

Statement dc:rights

• Baylor University works are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. Contact libraryquestions@baylor.edu for inquiries about permission.

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/2104/13180

OAI identifier oai:identifier

oai:baylor-ir.tdl.org:2104/13180