Synthesis and photoluminescence studies on YAl₃(BO₃)₄:Tb³⁺ phosphor

¹ Department of Physics, Anna University, MIT Campus, Chennai 600 044, Tamil Nadu, India
² Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu, India
³ Research and Development Laboratory, Department of Physics, Saveetha Engineering College, Chennai 602 105, Tamil Nadu, India

^a e-mail: ponnu76@rediffmail.com

Received: 11 June 2014
Revised: 18 September 2014
Accepted: 15 October 2014
Published online: 12 December 2014

Abstract

Terbium (Tb³⁺) doped yttrium aluminium borate phosphors (YAl₃(BO₃)₄) with different compositions such as YAl₃(BO₃)₄:Tb³⁺, Y_1−xAl₃(BO₃)₄:Tb_x³⁺ and YAl_(3−x)(BO₃)₄:Tb_x³⁺ (x = 1−8 mol.%) were synthesized using modified solid state reaction technique. The synthesized phosphor was studied using powder X-ray diffraction analysis (XRD), photoluminescence spectroscopy (PL), high resolution-scanning electron microscope (HR-SEM). Lattice parameters are calculated for the Tb³⁺ doped and substituted YAB phosphors using XRD analysis. The phosphor exhibits green emission at 572 nm with 375 nm of excitation. It is found that the Tb³⁺ ions substitution in the sites Y³⁺ and Al³⁺ ions in Y_1–xAl₃(BO₃)₄:Tb_x³⁺ and YAl_(3–x)(BO₃)₄:Tb_x³⁺ leads to overlapping of energy levels which affects the PL intensity of the phosphor significantly. Thus, phosphor synthesized with the composition YAl₃(BO₃)₄:Tb³⁺, acquires higher photoluminescence (PL) intensity when compared to Y_1–xAl₃(BO₃)₄:Tb_x³⁺ and YAl_(3–x)(BO₃)₄:Tb_x³⁺ phosphors. Temperature dependent PL property (thermal quenching studies) of YAl₃(BO₃)₄:Tb³⁺ was also performed up to 250 °C. Further, it is found that the PL intensity of the studied phosphor is comparable with commercial green phosphor. HR-SEM analysis demonstrates that the phosphors are grown as nanorods with an average diameter of 50–80 nm and length 250–500 nm.