Synthesis, characterization and applications of nanomaterials in the field of photocatalysis

Doctoral Thesis / Dissertation from the year 2011 in the subject Chemistry - Materials Chemistry, East China University of Science and Technology (-), language: English, abstract: Considerable effort has been made to design, fabricate, and manipulate nanostructuredmaterials by innovative approaches. The precise control of nanoscale structures will pave theway not only for elucidating unique size/shape dependent physicochemical properties but alsofor realizing new applications in science and technology. Nanotechnology offersunprecedented opportunities for improving our daily lives and the environment in which welive.This thesis mainly describes recent progress in the design, fabrication, and modificationof nanostructured semiconductor materials for environmental applications. The scope of thisthesis covers TiO2, Bi2O3 and BiOCl materials, focusing particularly on TiO2-basednanostructures (e.g., pure, doped, coupled, mesoporous, hierarchically porous, and orderedmesoporous TiO2).Mesoporous titania is of particular interest since this class of materials possesseswell-defined porosity and large specific surface areas. For photocatalytic degradation oforganics, these desirable properties are anticipated to improve the efficiency. So in the firstpart of work, I have synthesized the mesoporous titania by using poly ethylene glycol as atemplate in dilute acetic acid aqueous solution by hydrothermal process and investigated theeffect of PEG molecular weights and thermal treatment on the resultant structure andphotocatalytic activity. When the molecular weights of PEG vary from 600 to 20,000, theparticle sizes of mesoporous-TiO2 structure decrease from 15.1 to 13.3 nm and mean poresizes increase from 6.9-10.6 nm. The activities of these mesoporous-TiO2 photocatalystsprepared by using PEG are evaluated and compared with Degussa P-25 using chloro-phenolas a testing compound. [...]