Study of energy transfer from Bi3+ to Tb3+ in Y2O3 phosphor and its application for W-LED

Publication date: Available online 17 February 2020Source: Journal of Alloys and CompoundsAuthor(s): D.R. TaikarAbstractY2O3 activated with different activators were prepared by co-precipitation method. The prepared phosphors were characterized by XRD, SEM and photoluminescence (PL) techniques. The Tb3+ doped Y2O3 phosphor shows characteristic green emission due to 5D4 to 7Fj transitions of Tb3+ ion. The Bi3+ doped Y2O3 phosphor shows PL emission in blue region due to the transition between excited 3P1 state and ground state 1S0 of Bi3+ ion. The multiple systems of Tb3+emission lines in Y2O3:Tb3+ and two types of excitation and emission spectra of Y2O3:Bi3+ phosphors are due to two Y3+ sites in the host structure with C2 and S6 symmetries. Due to the addition of transition metal ion Bi3+ in Y2O3:Tb3+ lattice, the excitation efficiency is enhanced throughout the spectral range from 300 nm to 400 nm Bi3+ ions absorb N-UV radiation and, subsequently, the energy is transferred from the sensitizer Bi3+ to activator Tb3+ and emitted via 5D4 to 7Fj transitions of Tb3+ ion. From the spectral properties of Y2O3:Bi3+ and Y2O3:Tb3+, Bi3+, it is established that the prepared phosphors are useful in near UV excited LED (solid state lighting) application.Graphical abstract

Source: Journal of Alloys and Compounds - February 18, 2020 Category: Chemistry Source Type: research