A Comparative Study of SiO 2 :Tb 3+ @Gd 2 O 3 :Eu 3+ and Its Inverted Tb 3+ -Eu 3+ Core-Shell Phosphors.

How to effectively improve energy transfer efficiency and luminous intensity inspired us to synthesize a series of SiO 2 : x %Tb 3+ @Gd 2 O 3 : y %Eu 3+ samples, study their luminescence properties and interfacial energy transfer (IET), and compare with SiO 2 : x %Eu 3+ @Gd 2 O 3 : y %Tb 3+ . The results show that SiO 2 : x %Tb 3+ @Gd 2 O 3 : y %Eu 3+ can exhibit adjustable multicolor luminescence from red to green at different concentrations of Eu 3+ and Tb 3+ or under different excitation wavelengths, and there exists efficient IET from Tb 3+ to Eu 3+ in SiO 2 : x %Tb 3+ @Gd 2 O 3 : y %Eu 3+ and SiO 2 : x %Eu 3+ @Gd 2 O 3 : y %Tb 3+ , which improves the energy transfer efficiency and luminous intensity. In addition, the luminescence properties are different between SiO 2 :3%Tb 3+ @Gd 2 O 3 :3%Eu 3+ and SiO 2 :3%Eu 3+ @Gd 2 O 3 :3%Tb 3+ , and the energy transfer efficiency of Tb 3+ → Eu 3+ in SiO 2 :3%Tb 3+ @Gd 2 O 3 :3%Eu 3+ is obviously higher than that in SiO 2 :3%Eu 3+ @Gd 2 O 3 :3%Tb 3+ . The present study not only developed a kind of multicolor luminescent phosphor but also offered an important new strategy for improving the energy transfer efficiency and luminescent intensity.