Investigations of Eu3+ activated calcium dialuminate based phosphor-in-glass as an inorganic color converter for solid-state lighting applications

A red-emitting, transparent phosphor-in-glass was prepared using the traditional melt-quenching method by varying the phosphor-to-glass ratio. Europium doped CaAl4O7 phosphor was incorporated into the multicomponent tellurite glass. Structural study investigated by XRD shows the amorphous nature of the sample due to the glass component. Fourier-transform infrared spectroscopy (FTIR) and Raman measurements confirms the formation of glass by the presence of tellurite (Te-O) and borate (B-O) functional groups. The optical microscopy confirms the incorporation of phosphor into the glass matrix and formation of phosphor-in-glass (P-i-G) material. UV analysis confirmed the closeness in the refractive index between the phosphor particles and the glass matrix. The luminescence properties of incorporated phosphor were investigated using the photoluminescence (PL) measurements. High intense characteristic emission peaks around 617 nm were observed upon excitation at 393 nm due to the Eu3+ ions. Thermal stability of the P-i-G was examined up to 150 °C and it is able to retain till 80.4 % of the initial PL intensity recorded at room temperature. PL intensity were recorded for different electric power and it validated that the fabricated P-i-G can be used for enhancing the warm white light generation and application in display backlighting.