MgO-Y2O3:Eu composite ceramics with high quantum yield and excellent thermal performance

Abstract

MgO-Y2O3:Eu composite ceramics with high quantum yield and excellent thermal performance were successfully synthesized by vacuum sintering. All samples exhibited uniform composite microstructures and pure binary phase. Eu3+ ions were completely incorporated into Y2O3 phase, and the optimal Eu concentration is 15 at%. Sintered at 1800 °C, the fluorescent properties of MgO- z vol% Y2O3: Eu (z = 30, 40, 50, 60, 70, 100) composites proved to be independent on component proportion, including the similar fluorescence lifetimes (953–983 μs), quantum yield (70%−80%), and activation energy (ΔE) of thermal quenching (0.163 eV). Significantly, thermal conductivity of composites with 30 vol%, 50 vol% and 70 vol% MgO attained 11.58, 17.45, and 29.65 W/(m∙K) at room temperature, which are nearly 2, 3, and 5 times as high as that of 15 at% Eu:Y2O3 ceramic (5.90 W/(m∙K)), respectively, demonstrating their potential for application in high-power-density display and lighting technology.