Theoretical analysis of electron vibration interactions and study of photo physical properties in Ce3+ doped Ca2P2O7 nano phosphor capped with SHMP

Abstract

In the present manuscript, Calcium diphosphate phosphor doped with Cerium and capped with sodium hexametaphosphate has been reported. A theoretical analysis of electron vibration interactions in optical transitions of Ce3+ ions in Ca2P2O7 has been elaborated in brief. The main EVI parameters such as Huang’s Rhys factor and effective phonon energy were determined by evaluating the lowest 5d level of Ce3+ spectrum. The obtained values were used to model the shape of emission band along with estimation of zero phonon line. The fabricated nano phosphor was characterized by powder X-ray diffraction technique. Studies revealed that Ca2P2O7 crystallizes in tetragonal group with square anti prism symmetry. The crystal structure arrangement was found to be non linear in nature with two PO3 groups linked by bridging oxygen forming the diphosphate group. Transmission electron microscopy observations explored nano structural features of the synthesized nano phosphor compound. A study involving SAED and HRTEM on isolated particles was carried out to validate the stabilization of the tetragonal phase. The phosphate functional group of the host was probed by Fourier transform infrared microscopy. Optical properties were examined by evaluating the photoluminescence excitation and emission spectra. Broad emission peaks were observed around 326 nm and 347 nm because of 4f-5d transitions of rare earth activator Ce3+. With the help of TL glow curve measurements, the trap depths were calculated employing peak shape method. Lifetime calculation for the nano phosphor indicates that the aforementioned compound has promising potential for solid state lighting and optoelectronic applications.