Luminescence characteristics of white light emitting BaGa2O4:Dy3+ phosphors for LEDs and stress sensing applications

Abstract

A series of single-phase white-light-emitting BaGa2O4:xDy3+(x = 0.1,0.3,0.5,0.7,1) phosphors have been synthesised using solid-state reaction technique. The structural studies using the X-ray diffraction (XRD) technique indicate that the phosphors are single-phase and Scanning Electron Microscope (SEM) study reveals that the particle size is in micrometer range. The phosphors emit white light with peaks at 346 nm, 357 nm, 386 nm, and 426 nm generated by Dy3+ ion transitions (6H15/2 → 6P7/2), (6H15/2 → 6P9/2), (6H15/2 → 4F7/2+4I13/2) and (6H15/2 → 4G11/2). The colour coordinates calculated for BaGa2O4:xDy3+ (x = 0.5,0.7) phosphors are identical to the conventional white light. BaGa2O4:Dy3+ exhibits good Mechanoluminescence (ML) response at varied impact velocities for both unirradiated and gamma-irradiated samples. This characteristic is reasonably beneficial in the development of damage and pressure sensors. Thermoluminescence (TL) analysis shows a single glow curve of similar shape irrespective of increasing irradiation, and the TL parameters have been calculated.