Photoluminescence characteristics of Sm3+/Eu3+ co-doped LPZABS glasses for solar cell applications

A series of Sm3+/Eu3+ co-doped LPZABS (lithium lead zinc alumino borosilicate) transparent glasses were synthesized by the melt quench method. Fluorescent characteristics and energy transfer mechanisms were analyzed thoroughly. The amorphous nature of the glasses was confirmed from the observed X-ray diffraction patterns. An expansion in photoluminescence (PL) excitation of Eu3+ ions was observed on sensitizing it with Sm3+ ions in the title compounds. The PL emission spectra obtained for different excitations show bands due to Sm3+ and Eu3+ ions with increment in intensity on increasing Eu3+ ion concentration. On implementing the Dexter energy transfer formula & Reisfeld's approximation to PL emission spectra and the Inokuti-Hirayama (I-H) model to PL decay profiles, the dipole-dipole interaction among activator and sensitizer is revealed. Chromaticity coordinates (CIE) gradually relocate from the orange to the red region on increasing Eu3+ ion concentration in Sm3+/Eu3+ co-doped LPZABS glasses. The Sm3+/Eu3+ co-doped LPZABS glasses have the potential for downshifting of n-UV & blue exciting photons into visible red color photons which make it useful for copper phthalocyanine (CuPc) solar cell applications.