• Login
    JavaScript is disabled for your browser. Some features of this site may not work without it.
    Ferroelectric Barium Titanate For Semiconductor Photocatalytic Application 
    •   QMRO Home
    • Queen Mary University of London Theses
    • Theses
    • Ferroelectric Barium Titanate For Semiconductor Photocatalytic Application
    •   QMRO Home
    • Queen Mary University of London Theses
    • Theses
    • Ferroelectric Barium Titanate For Semiconductor Photocatalytic Application
    ‌
    ‌

    Browse

    All of QMROCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects
    ‌
    ‌

    Administrators only

    Login
    ‌
    ‌

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Ferroelectric Barium Titanate For Semiconductor Photocatalytic Application

    View/Open
    Cui_Yongfei_PhD_Final_090915.pdf (6.304Mb)
    Publisher
    Queen Mary University of London
    Metadata
    Show full item record
    Abstract
    Semiconductor photocatalysis has received extensive attention due to its wide applications in water and indoor air purification, solar fuel production, etc. Charge carrier separation is a crucial step in semiconductor photocatalysis and influences the overall efficiency. It has been demonstrated that internal depolarisiation field of ferroelectric materials can drive spatial separation of charge carriers, which results in spatial separation of reduction and oxidation reactions, and improved charge carrier separation. In this thesis, ferroelectric barium titanate was chosen and its photocatalytic performance in decolourisation of organic dye molecules was investigated. Photodeposition method was adopted to deposite silver nanoparticles on the surface of barium titanate. Silver modified barium titanate showed increased photodecolourisation rate compared with bare barium titanate due to its role of electron traps and hindered charge carrier recombination. A simple thermal treatment was used to alter the phase composition of the as-received barium titanate. Samples which contained more ferroelectric tetragonal phase were found to possess higher photocatalytic activity compared with non-ferroelectric samples. This was associated with stronger ferroelectricity after thermal treatment, which enhanced dye molecule adsorption and aid charge carrier separation. The mechanism and intermediates generated in photodegradation of Rhodamine B with silver modified ferroelectric barium titanate were studied. Cleavage of chromophore was demonstrated to dominate in the initial process. Benzoic acid was identified as the main intermediate and no siginificant discrepancy in intermediates distribution between ferroelectric photocatalytic system and non-ferroelectric system was observed. The influence of ferroelectric dipole of barium titanate on photocatalytic activity of heterostructured barium titanate/hematite was also studied. The synthesised heterostructured barium titanate/hematite showed higher photodcolourisation rate than both barium titanate and hematite. This phenomenon was attributed to the improved charge carrier separation and extended charge carrier lifetime arising from heterojunction and an interaction between the ferroelectric dipole and the carriers in the hematite.
    Authors
    Cui, Yongfei
    URI
    http://qmro.qmul.ac.uk/xmlui/handle/123456789/9530
    Collections
    • Theses [3315]
    Copyright statements
    The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author
    Twitter iconFollow QMUL on Twitter
    Twitter iconFollow QM Research
    Online on twitter
    Facebook iconLike us on Facebook
    • Site Map
    • Privacy and cookies
    • Disclaimer
    • Accessibility
    • Contacts
    • Intranet
    • Current students

    Modern Slavery Statement

    Queen Mary University of London
    Mile End Road
    London E1 4NS
    Tel: +44 (0)20 7882 5555

    © Queen Mary University of London.