Synthesis, photoluminescence, cathodoluminescence, and thermal properties of novel Tb3+-doped BiOCl green-emitting phosphors

Abstract

Tb3+-doped BiOCl phosphors were synthesized by a facile solid-state reaction method. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), photoluminescence (PL) and cathodoluminescence (CL) spectra, and PL thermal stability. Under 377 nm near-ultraviolet light excitation, all the samples showed the characteristic green emissions of Tb3+ ions owing to the 5D4 → 7FJ (J = 6, 5, 4, 3) transitions. The dependence of PL emission intensity on the Tb3+ doping concentration was investigated and the optimal doping concentration was found to be 9 mol%. With the help of theoretical calculation, the critical distance was determined to be about 10.58 Å and the concentration quenching was dominated by multipole-multipole interaction. Furthermore, thermal stability of these phosphors was investigated by measuring the temperature-dependent PL spectra. In addition, these Tb3+-doped BiOCl phosphors also exhibited strong CL green emissions, and the CL emission intensity did not show saturation with the increase of accelerating voltage and filament current. These results indicated that the Tb3+-doped BiOCl phosphors may have potential applications in white light-emitting diodes (LEDs) and field emission displays (FEDs) as green-emitting phosphors.