Energy transfer and photo/cathodoluminescence performances investigation of a luminescent material Ce3+/Tb3+ co-doped Na2Ca2Si2O7 for multifunctional applications

Abstract

Exploring novel efficient luminescence materials for applications in solid-state lighting and display is highly meaningful and important thing. Herein, we report a new Ce3+/Tb3+ co-doped Na2Ca2Si2O7 (NCSO) phosphor with high energy transfer and efficient luminescence performances. The co-doped samples own broad excitation spectra covering the whole near-UV region, and the emission spectra can be adjusted from blue to green by increasing Tb3+ concentration. The decrease of lifetime and the ratio of Ce3+ and Tb3+ emission intensity indicate the samples have high energy transfer efficiency, which can reach 90%. The mechanism of energy transfer between Ce3+ and Tb3+ was demonstrated in detail and it is attributed to dipole-dipole interaction. According to the temperature-dependent PL spectra of NCSO: 0.03Ce3+,0.12 Tb3+, the Tb3+ emission intensity still remained about 71% of initial intensity at 225 °C. Meanwhile, the Ce3+/Tb3+ emission intensity ratio of NCSO: 0.03Ce3+, 0.05 Tb3+ exhibits a linear correlation from 298 K to 498 K with a high sensitivity of 0.59% K−1. The fabricated white LED emits dazzling white light with low CCT 4353K and high CRI 80.2, and the luminous efficiency is 37.61 lm/W. The CL spectra under different accelerating voltage with various probe current reveal that the phosphor possesses high saturation voltage and saturation current. Under high-energy electrons bombing, the phosphor displays excellent ageing resistance. The outstanding performances of the phosphors on PL and CL provide the possibility for application in LED and FEDs.