Energy transfer based enhanced red emission intensity from (Eu3+, Tb3+):LFBCd optical glasses

• Published in: Journal of luminescence 2013-05, Vol.137, p.15-21
• Main Authors: Naresh, V., Buddhudu, S.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Decay curves; Diffraction; Emission; Energy levels; Energy transfer; Exact sciences and technology; Excitation; Glass; Luminescence; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; X-rays
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2012.12.060

Present paper reports on the red emission enhancement by means of an energy transfer process in Eu3+ co-doped with Tb3+ in LFBCd glasses. The structural and photoluminescence properties of these glasses have been carried out from the measurement of X-Ray diffraction, excitation and emission spectra and also from the red emission transition lifetime. The PL spectrum of Eu3+ doped LFBCd glass has revealed a bright red emission at 612nm (5D0→7F2) with an excitation at 393nm (7F0→5L6). With Tb3+ ion singly doped glass has shown a prominent green emission at 547nm (5D4→7F5) with an excited at λexci=377nm (7F6→5G6). LFBCd glasses having Eu3+(1mol%) co-doped with Tb3+ ion (in 0.1, 0.5, 1mol%) at an excitation of λexci=377nm, have exhibited an energy transfer from Tb3+ to Eu3+ ions hence causing an enhancement in red emission from Eu3+. The mechanism involved in this energy transfer process from terbium to europium ions has been explained in terms of an energy level diagram and from lifetime profiles. ► The non-radiative energy transfer from Tb3+ (5D4) to Eu3+ (5D1) in the LFBCd glass matrix has been explained. ► Luminescence of Eu3+ attributed to 5D0→7FJ transitions were intensified by the incorporation of Tb3+ ion. ► Occurrence of energy transfer was confirmed from the presence of optical band of Tb3+ (5D4) in the excitation spectra. ► Due to energy transfer, lifetime of Eu3+ ion has been increased and this confirms Tb3+ acts as a sensitiser.