Title: A Single-Phased Emission-Tunable Phosphor Ca(9)Y(PO(4))(7):Eu(2+),Mn(2+) with Efficient Energy Transfer for White-Light-Emitting Diodes
Authors: Huang, Chien-Hao
Chen, Teng-Ming
Liu, Wei-Ren
Chiu, Yi-Chen
Yeh, Yao-Tsung
Jang, Shyue-Ming
Department of Applied Chemistry
Issue Date: 1-Jan-2010
Abstract: A series of single-composition emission-tunable Ca(9)Y(PO(4))(7):Eu(2+),Mn(2+) phosphors were synthesized by solid-state reaction. The energy transfer from Eu(2+) to Mn(2+) in Ca(9)Y(PO(4))(7) host matrix was studied and demonstrated to be a resonant type via a dipole-quadrupole mechanism with the critical distance of similar to 11 angstrom. The wavelength-tunable white light can be realized by coupling the emission bands centered at 486 and 638 nm ascribed to the contribution From Eu(2+) and Mn(2+), respectively. By properly tuning the relative composition of Eu(2+)/Mn(2+), chromaticity coordinates of (0.31, 0.33) can be achieved under excitation at 250-440 nm. Moreover, white-light-emitting diodes were fabricated through the integration of 365 nm chips and single composition white-light-emitting phosphors (Ca(0.975)Eu(0.01)Mn(0.015))(9)Y(PO(4))(7) into a single package shows a cool white light of 7200 K, color rendering index of 76, and color coordinates of (0.30, 0.31) close to that of ideal white light can be achieved.
URI: http://dx.doi.org/10.1021/am900668r
ISSN: 1944-8244
DOI: 10.1021/am900668r
Volume: 2
Issue: 1
Begin Page: 259
End Page: 264
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