TY - JOUR

T1 - LiBa12(BO3)7F4 (LBBF) crystals doped with Eu3+, Tb3+, Ce3+: structure and luminescence properties

AU - Bekker, Tatyana B

AU - Ryadun, Alexey A

AU - Davydov, Alexey V

AU - Rashchenko, Sergey V

N1 - This work was supported by the Russian Science Foundation, grant no. 21-19-00097, https://www.rscf.ru/project/21-19-00097/. The work was carried out using the equipment of the Laboratory “Molecular Design and Ecologically Safe Technologies” at Novosibirsk State University.

PY - 2023/6/20

Y1 - 2023/6/20

N2 - The luminescent properties of single crystals and polycrystalline samples of LiBa12(BO3)7F4 (LBBF) doped and co-doped with Eu3+, Tb3+, and Ce3+ have been studied in order to disclose their potential for application in white light-emitting diodes. Deciphering of LBBF:Eu3+ crystal structure (P42/mbc) makes it possible to determine the scheme of heterovalent isomorphic substitution 3Ba2+ ← 2Eu3+ + □, □ - vacancy in barium sites. Luminescent properties of LBBF crystals co-doped with Eu3+, Tb3+, Ce3+ and Eu3+, Tb3+ are compared. Both crystals demonstrate the luminescence close to day light with CIE coordinates and correlated color temperature (0.280; 0.305), 9232 K for LBBF:Eu3+,Tb3+,Ce3+ and (0.353; 0.390), 4849 K for LBBF:Eu3+,Tb3+ at 300 K at 370 nm excitation. The study of polycrystalline samples LBBF:Ce3+, LBBF:Tb3+, and LBBF:Eu3+, using X-ray diffraction, shows that the homogeneity regions of solid solutions differ significantly. In solid solutions LBBF:Tb3+ and LBBF:Eu3+, a gradual change in symmetry in the "tetragonal → orthorhombic → tetragonal" series takes place as the concentration of the dopant increases. When excited at a wavelength 395 nm, LBBF:Eu3+ samples with the content of Eu3+ 0.5 wt% and 2 wt% demonstrate intense red light with a high quantum yield of 63 and 60%, respectively, which allows them to be used as red components of composite phosphors for white LEDs.

AB - The luminescent properties of single crystals and polycrystalline samples of LiBa12(BO3)7F4 (LBBF) doped and co-doped with Eu3+, Tb3+, and Ce3+ have been studied in order to disclose their potential for application in white light-emitting diodes. Deciphering of LBBF:Eu3+ crystal structure (P42/mbc) makes it possible to determine the scheme of heterovalent isomorphic substitution 3Ba2+ ← 2Eu3+ + □, □ - vacancy in barium sites. Luminescent properties of LBBF crystals co-doped with Eu3+, Tb3+, Ce3+ and Eu3+, Tb3+ are compared. Both crystals demonstrate the luminescence close to day light with CIE coordinates and correlated color temperature (0.280; 0.305), 9232 K for LBBF:Eu3+,Tb3+,Ce3+ and (0.353; 0.390), 4849 K for LBBF:Eu3+,Tb3+ at 300 K at 370 nm excitation. The study of polycrystalline samples LBBF:Ce3+, LBBF:Tb3+, and LBBF:Eu3+, using X-ray diffraction, shows that the homogeneity regions of solid solutions differ significantly. In solid solutions LBBF:Tb3+ and LBBF:Eu3+, a gradual change in symmetry in the "tetragonal → orthorhombic → tetragonal" series takes place as the concentration of the dopant increases. When excited at a wavelength 395 nm, LBBF:Eu3+ samples with the content of Eu3+ 0.5 wt% and 2 wt% demonstrate intense red light with a high quantum yield of 63 and 60%, respectively, which allows them to be used as red components of composite phosphors for white LEDs.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85161642881&origin=inward&txGid=a8209a6dca9f525f636d31292869c734

UR - https://www.mendeley.com/catalogue/1d0970a9-723c-32a5-837e-fc8982cf0a6f/

U2 - 10.1039/d3dt01279d

DO - 10.1039/d3dt01279d

M3 - Article

C2 - 37265343

VL - 52

SP - 8402

EP - 8413

JO - Dalton Transactions

JF - Dalton Transactions

SN - 1477-9226

IS - 24

ER -