The present investigation aims to demonstrate the potentiality of Ca3Y2Si3O12 doped with Ce3+ and Tb3+ along with Tb3+ and Ce3+ co-doped phosphors, which are prepared by a sol-gel method. Photoluminescence (PL) spectra revealed a brighter and broader violet-blue emission from the Ce3+ [5d(D-2) -> F-2(5/2,7/2)] and an intense sharp green emission (545 nm) from the Tb3+ (D-5(4) -> F-7(5)) doped phosphors. For Tb3+ and Ce3+ co-doped phosphors, a strong green emission (D-5(4) -> F-7(5)) was observed upon excitation with a UV wavelength (242 nm). An energy transfer phenomenon from Ce3+ to Tb3+ was observed in these co-doped nanocrystalline phosphors. It was also observed that their PL intensity depends on the doping concentration of Ce3+, while the concentration of Tb3+ is fixed. The mechanism involved in the energy transfer between Ce3+ and Tb3+ was explained with an energy level diagram. For these phosphors, X-ray diffraction and transmission electron microscopy were carried out to understand their structural properties. (C) 2009 The Electrochemical Society. [DOI:10.1149/1.3215985] All rights reserved.