摘要： In this paper, hollow double-shelled TiO2:x%Eu3+@SiO2:y%Tb3+ nanospheres (C1-Ti-x/Si-y) were fabricated using carbon spheres as hard template followed by a two-step sol-gel coating process. The results demonstrate that there is strong interaction between inner TiO2 layer and outer SiO2 layer, which can be characterized by the high surface content of Ti-O-Si bonds. The strong interaction makes it possible to achieve efficient energy transfer from Tb3+ to Eu3+ ions through crossing the double-shelled interface. The interfacial energy transfer (IET) efficiency from Tb3+ to Eu3+ions is strongly influenced by the doping concentration of Eu3+ ions whose maximum is determined to be 30.2%. Furthermore, the surface of inner TiO2 layer is modified by the outer SiO2 layer through this strong interaction, which significantly enhances the emission intensity and suppresses the concentration quenching of Eu3+ ions. Under 377 nm excitation, C1-Ti-x/Si-y simultaneously exhibits red and green emissions derived from Eu3+ and Tb3+ ions, respectively. Moreover, by varying doping concentration of Tb3+ and Eu3+ ions, the luminescence color of the samples can be tuned from green to orange and red. The characterization results show that our proposed phosphors may provide potential applications in tissue imaging.