Journal Articles - Natural Science - 2020

Permanent URI for this collection

http://repository.vlu.edu.vn:443/handle/123456789/113

Browse

Browsing Journal Articles - Natural Science - 2020 by Author "Do Thanh Tien"
  • Publication
    Luminescence and Thermal-Quenching Properties of Red-Emitting Ca2Al2SiO7:Sm3+ Phosphors
    ( 2020)
    Nguyen Manh Son
    ;
    Do Thanh Tien
    ;
    Nguyen Thi Quynh Lien
    ;
    Vu Xuan Quang
    ;
    Nguyen Ngoc Trac
    ;
    Tran Thi Hong
    ;
    Ho Van Tuyen
    Ca2Al2SiO7:x.Sm3+ (x = 0.5, 1.0, 1.5, 2.0, 2.5, and 3.5 mol.%) (CAS:x.Sm3+) phosphors were synthesized by a solid-state reaction technique. The structure, photoluminescence properties and thermal stability of phosphors were investigated in detail. Results of X-ray diffraction show that CAS:x.Sm3+ materials have a single-phased tetragonal structure, and an expansion of the unit cell relates to the increasing of Sm3+ concentration. Photoluminescence study displayed that the CAS:x.Sm3+ phosphors reach the highest emission intensity at 1.5 mol.% Sm3+ and achieved the luminescence quenching phenomenon a higher concentration. The dominant interaction mechanism of the concentration quenching process is determined due to the dipole–dipole interaction, and the critical transfer distance (Rc) is 26.7 A ° . The temperature dependence of photoluminescence spectra indicates that the Ca2Al2SiO7:Sm3+ (1.5 mol.%) phosphor possess good thermal stability, and that the activation energy is around 0.12 eV (968 cm 1). Several characteristic vibrations in the 200–1000-cm 1 region were observed by Raman spectra, and the color chromaticity coordinates of the samples were also calculated and discussed.