Synthesis, characterization, and exploring optical pathways of centrosymmetric Li2MgP2O7/ZnMgP2O7: Eu3+pyrophosphate phosphor for LEDs applications

Abstract

The present study reports the synthesis of two new centrosymmetric pyrophosphates Li2MgP2O7:Eu3+and ZnMgP2O7:Eu3+compounds by the wet-chemical method. Structural confirmation and phase purity were primarily investigated by XRD analysis and FT-IR. Li2MgP2O7:Eu3+ belongs to the P21/m space group of the monoclinic crystal system, while ZnMgP2O7:Eu3+ phosphor crystallizes in a monoclinic system with a P21/n space group. Herein, these compounds exhibit strong optical absorption over a wavelength range of 200–800 nm. Photoluminescence emission spectra (PL) interestingly reveal their structural elucidation and optical trait to uncover their commercial applications. At 362 nm excitation, a series of emission bands were recorded at different regions. The dominant greenish emission peak was found at 548 nm. We have also recorded another emission peak at 598 nm, 612 nm, and 617 nm, which were much weaker than the former profile peak. The peak at 598 nm is attributed due to 5D0 -7F1 electric dipole transitions. Whereas, the peak at 617 nm belongs to the forbidden f-f transitions, ascribed due to 5D0 -7F2. The CIE chromaticity coordinates explains the nature of the color bands of phosphors based on their particular wavelengths. The Judd-Ofelt (J–O) strongly suggested that the prepared phosphors will act as a potential candidate for the fabrication of illuminating devices and the construction of w-LEDs.