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Publication - Professor Mike Ashfold

    Introducing carbon dots to moderate the blue emission from zinc vanadium oxide hydroxide hydrate nanoplates

    Citation

    Huang, P, Yuan, G, Wei, T, Li, J & Ashfold, M, 2018, ‘Introducing carbon dots to moderate the blue emission from zinc vanadium oxide hydroxide hydrate nanoplates’. RSC Advances, vol 8., pp. 20686-20691

    Abstract

    The relative intensity of the blue component of the total emission from
    light-emitting diodes (LEDs) can be an important factor when assessing
    their biological safety. Carbon quantum dots (CQDs) are compatible with
    many materials and present a high density of multiple surface states;
    the incorporation of such CQDs thus offers a route to modifying the
    emission from a given LED matrix. Here we report the fabrication of
    stable CQD/zinc pyrovanadate (Zn3(OH)2V2O7·2H2O) nanoplate composites via
    a facile hydrothermal route. Structural and morphological analyses
    confirm that the nanoplates are hexagonal phase and grew normal to the
    [0001] direction. X-ray photoemission spectroscopy, Raman and infrared
    spectroscopy demonstrate that the CQDs combine with nanoplates via
    surface carbon–oxygen bonds. Wavelength resolved photoluminescence
    measurements show that the relative intensity of the blue (2.93 eV)
    component of the emission associated with the nanoplates is
    significantly reduced by incorporating CQDs. We suggest that this
    reduction arises as a result of preferential trapping of the higher
    energy photoelectrons by surface defects on the CQDs.

    Full details in the University publications repository