Down-conversion characteristics of Eu3+ doped M2Y2Si2O9 (M = Ba, Ca, Mg and Sr) nanomaterials for innovative solar panels

Down-conversion properties of Eu3+ doped M2Y2Si2O9 (M = Ba, Ca, Mg, Sr) phosphors have been investigated in detail. These phosphors were synthesized via the simple, fast and cost-effective sol-gel technique at a temperature of 950 degrees C. Color coordinates and emission color can be altered by the varying concentration of dopant ion in Ca2Y2Si2O9 phosphor. Optimum luminescence intensity was obtained when doping 0.03 mol of Eu3+ ion. Using the excitation wavelength of 395 nm, these silicates showed strong red color, pure and sharp spectral peaks in visible region due to D-5(0)-> F-7(1-3) transitions of Eu3+ present in the lattice. Effect of reaction temperature on luminescence was also analyzed for these phosphors. The sharp peaks in the X-ray diffraction pattern indicated the high crystallinity of prepared phosphors. Ca2Y2Si2O9 has shown an orthorhombic crystal structure. The FTIR results confirmed the metal-oxygen vibrational modes available in the range of 400-1600 cm(-1). Transmission electron microscopy images have revealed that the variation of alkaline earth metal provided a very different crystal structure. Excellent down conversion response of these phosphor materials can provide a great significance in the application of the coming solar devices.