Broadband Downconversion of Ultraviolet Light to Near-Infrared Emission in Bi3+–Yb3+-Codoped Y2O3 Phosphors
Abstract:The metal ion Bi3+ has been shown to be an efficient broadband sensitizer for Yb3+ ion in the Y2O3 host lattice. Upon ultraviolet-light excitation in the allowed 1S0→3P1 transition of Bi3+ ions, the characteristic near infrared luminescence of Yb3+ ions due to the 2F5/2→2F7/2 transition was observed as a result of energy transfer from Bi3+ to Yb3+ ions. It demonstrates that cooperative downconversion can be realized for Bi3+–Yb3+ coupling. Yb3+-concentration-dependent quantum efficiency was evaluated and the maximum efficiency reached 173.8%. These phosphors are promising for the enhancement of energy efficiency of crystalline Si solar cells via spectrum shifting.
Document Type: Research Article
Affiliations: MOE Key Lab of Specially Functional Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, China
Publication date: 2011-03-01