Molecular assembly of red and green nanophosphors from amine-functionalized covalent linking hybrids with emitting centers of Eu3+ and Tb3+ ions

We report a novel technology for fabricating sol–gel derived nano-scale molecular hybrid materials that contain NHC(O)NH groups anchored to a silica network. The modified 2-amino pyridine is grafted by 3-(triethoxysilyl)-propyl isocyanate and applied to coordinate to RE3+ (Eu3+, Tb3+) through nitrogen atoms of the heterocycle of pyridine group and further formed SiO backbones after hydrolysis and polycondensation processes. For analogy and luminescence efficiency purpose, we added 1,10-phenanthroline to the above hybrids in order to increase the conjugating effects and sensitize rare earth ions emissions. IR, ultraviolet absorption and luminescence spectra were utilized to characterize the structure and photophysical properties of the obtained hybrid material and the above spectroscopic data reveal that the triplet energy of 1,10-phenanthroline in this favorable hybrid system matches with the emissive energy level of RE3+.