Photoluminescence and thermoluminescence investigations of Ca₃B₂O₆: Sm³⁺phosphor

Abstract

Sm3+ doped Ca3B2O6 phosphors have been synthesized by combustion method. X-ray diffraction (XRD), photoluminescence (PL), UV–Vis spectroscopy and thermoluminescence (TL) have been used to study the structural, luminescence and optical properties of the phosphors. Under 400 nm excitation, the phosphor shows characteristic emission for Sm3+ ion (4G5/2 → 6Hj/2, j = 5, 7, 9 and 11) with the main orange-red emission peak at 600 nm corresponding to the 4G5/2 → 6H7/2 transition state of the Sm3+ ion. The optimum molar concentration and maximum critical distance between the Sm3+– Sm3+ ions were found to be 3 mol.% and 20.098 Å, respectively. The phosphor can be efficiently excited by near UV chips for their potential use in solid state lighting. The calculated CIE coordinates (0.60, 0.40) were found to be in the orange-red spectrum region. The thermoluminescence studies were carried out after irradiating the phosphor by gamma rays in the dose range of 10–5000 Gy. The glow peak was deconvoluted by the TLAnal program and the kinetic parameters associated with the deconvoluted peaks were evaluated.