Structural and luminescence properties of Mn2+ ions doped calcium zinc borophosphate glasses

Abstract

Calcium zinc borophosphate glasses (CaZnBP) doped with various concentrations of Mn2+ ions and borate and phosphate as variable were prepared using conventional melt quenching technique. The structure of obtained glasses were examined by means of use: X-ray diffraction (XRD) and fourier transform infrared (FT-IR). XRD analysis confirmed amorphous nature of glass samples. The FT-IR spectra reveals the presence of both borate and phosphate vibrational modes in the prepared glasses. The doping of Mn2+ ions (2-10 mol%) shows no significant changes in the main IR vibrational bands. Optical properties were studied by measuring the near infrared photoluminescence (PL) spectra. CaZnBP glasses exhibited intense green emission peak (582 nm) (tetrahedral symmetry), which is assigned to a transition from the upper T-4(1g) -> (6)A(1g) ground state of Mn2+ ions. As the concentration of Mn2+ ions increases, the emission band increases from 582 nm to 650 nm and exhibited a red light emission (octahedral symmetry). The decay curves of T-4(1g) level were examined for all concentrations and the measured lifetimes are found to depend strongly on Mn2+ concentrations. From the emission characteristic parameters of (6)A(1g) (S) level, it shows that the CaZnBP glasses could have potential applications as luminescent optical materials, visible lasers and fluorescent display devices.