Full-Color Phosphors from Europium(III)-Based Organosilicates

Room-temperature white light emission can be obtained from a family of europium-containing hybrid materials called di-ureasils—organically modified silicates in which oxyethylene chains of different length are grafted by means of urea crosslinks to the siliceous backbone. It is demonstrated that the emission color may be tuned by either adjusting the amount of europium salt incorporated or by varying the excitation wavelength. The Judd–Ofelt intensity parameters are obtained and considered together with the decay rates and an interpretation of the physical meaning of the observed behavior is offered.