High-efficiency energy transfer in the strong orange-red-emitting phosphor CeO 2 :Sm 3+ , Eu 3

• Published in: RSC advances 2023-11, Vol.13 (49), p.34510-34519
• Main Authors: Van Hai, Nguyen, Khanh Linh, Nguyen Thi, Hien, Dinh Thi, Hoan, Bui Thi, Tu, Nguyen Minh, Pham, Vuong-Hung, Nguyen, Duy-Hung, Anh, Vu Tuan, Van, Hoang Nhu
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/D3RA07567B

High-efficiency energy transfer (ET) from Sm 3+ to Eu 3+ leads to dominant red emission in Sm 3+ , Eu 3+ co-doped single-phase cubic CeO 2 phosphors. In this work, a series of Sm 3+ singly and Sm 3+ /Eu 3+ co-doped CeO 2 cubic phosphors was successfully synthesized by solution combustion followed by heat treatment at 800 °C in air. The crystal structure, morphology, chemical element composition, and luminescence properties of the obtained phosphors were investigated using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and photoluminescence analysis. Under 360 nm excitation, the Sm 3+ singly doped CeO 2 phosphor emitted strong yellow-red light at 573 nm ( 4 G 5/2 – 6 H 5/2 ) and 615 nm ( 4 G 5/2 – 6 H 7/2 ). Meanwhile, the CeO 2 :Sm 3+ , Eu 3+ phosphors showed the emission characteristic of both Sm 3+ and Eu 3+ , with the highest emission intensity at 631 nm. The emission intensity of Sm 3+ decreased with increasing Eu 3+ content, suggesting the ET from Sm 3+ to Eu 3+ in the CeO 2 :Sm 3+ , Eu 3+ phosphors. The decay kinetics of the 4 G 5/2 – 6 H 5/2 transition of Sm 3+ in the CeO 2 :Sm 3+ , Eu 3+ phosphors were investigated, confirming the high-efficiency ET from Sm 3+ to Eu 3+ (reached 84%). The critical distance of energy transfer ( R C = 13.7 Å) and the Dexter theory analysis confirmed the ET mechanism corresponding to the quadrupole–quadrupole interaction. These results indicate that the high-efficiency ET from Sm 3+ to Eu 3+ in CeO 2 :Sm 3+ , Eu 3+ phosphors is an excellent strategy to improve the emission efficiency of Eu 3+ .