Fig. 1. Crystal structure of Cs₃GdGe₃O₉ and coordination environments diagram of GdO₆ and GeO₄

Fig. 2. XRD patterns and magnified XRD patterns of CGGO：xBi³⁺ （0.02≤x≤0.1）samples

Fig. 3. Normalized excitation and emission spectra and fluorescence lifetime decay curve of CGGO：0.04Bi³⁺

Fig. 4. XRD patterns and magnified XRD patterns and crystal cell parameter variation diagram of CGLGO：0.04Bi³⁺（0.1≤y≤0.9）samples

Fig. 5. Diffuse reflectance spectra of CGGO，CGGO：0.04Bi³⁺，CGL_0.5GO：0.04Bi³⁺ and band gap diagram of phosphor sample at y=0，y=0.5

Fig. 6. Vary diagram of spectral behavior of CGLGO（0.1≤y≤0.9）solid solution phosphors

Fig. 7. Variable temperature spectra and temperature vary curve of CGLGO：xBi³⁺（x=0.04，y=0）