Luminescence and temperature-sensing properties of Y4GeO8:Bi3+,Eu3+ phosphor

In this paper, Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor with dual emission centers was elaborated via conventional solid-state reaction technology. Thorough research on the structure, morphology, and luminous properties of Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor, the potential applications in optical thermometry were investigated by means of fluorescence intensity ratio and thermochromic techniques. Under 290 and 347 nm excitation, Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor presents broadband emission from 3 P 1 → 1 S 0 transition of Bi 3+ ions and characteristic emission peaks from 4f–4f transition of Eu 3+ ions. Outstanding temperature-sensing capabilities are acquired from Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor. The maximum relative sensitivity ( S r ) can attain 1.51% K −1 ( λ ex = 290 nm). With temperature raising (303–513 K), the emitted color of Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor ( λ ex = 290 nm) shifts from faint yellow to red with a high chromaticity shift (0.180), which can be distinguished by the unaided eye clearly. Our results indicate that Y 4 GeO 8 :Bi 3+ ,Eu 3+ phosphor has potential applications in optical temperature measurement and high-temperature safety marker.