Highly efficient and thermally conductive phosphor in glass based on two-component regulatory and h-BN addition

Abstract

Achieving laser-driven solid-state lighting with higher brightness and laser power density engenders new requirements for higher-performance phosphor conversion materials. In this study, a highly efficient and thermally conductive tellurite phosphor-in-glass (PIG) added with hexagonal boron nitride (h-BN) was prepared for high-power laser driving. Reduction in the thermal expansion coefficient and refractive index matching with phosphor were realized by two-component regulation of the tellurite glass, which contributed to an enhanced laser irradiation threshold and luminous efficiency of the PIG. Furthermore, the micron h-BN powder, which served as a heat dissipation material and light scattering center, was uniformly dispersed within the PIG by stirring, which increased the thermal conductivity of the composite by 42 %. Microstructural characterization and XRD analysis indicated the ideal compound effect of h-BN and the integrity of the phosphor crystal phase. Notably, under irradiation with a high-power laser, the thermal stability of the composite material was significantly improved, and the luminous efficiency increased to 183.2 lm/W. Therefore, through component regulation and process optimization, the h-BN-added tellurite PIG acquired a high laser irradiation threshold and superior luminous efficiency, making it promising for applications in laser-driven white lighting.