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Broadening Phosphor-Converted Light-Emitting Diode Emission: Controlling Disorder

Journal Article


Abstract


  • Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are a highly efficient perspective NIR light source, with application hindered by a narrow emission band. In this work, we broaden the emission of a new series of NIR phosphors by controlling crystal structure disorder through cation cosubstitution. By substituting Ga3+with (Al0.68In0.32)3+, we create a Ga2-x(Al0.68In0.32)xO3:Cr3+phosphor series in which the average crystal size is maintained, while cation disorder varies. The increased deviation of the cation radii in the substitution leads to increased electron-phonon coupling, with a resulting emission spectrum covering the 650-1000 nm range with a 30% increase in the emission full width at half-maximum (FWHM) and a relatively high internal quantum efficiency of ���80%. A transition from the �� phase to the �� phase, which differs in structure from the undoped parent, is created by the application of high pressure and possesses ultra-broad-band emission and an FWHM of ���190 nm. This work shows that the emission bandwidth can be controlled through disorder and its influence on the Stokes shift, as captured by the effective Huang-Rhys factor.

Publication Date


  • 2022

Citation


  • Chang, C. Y., Majewska, N., Chen, K. C., Huang, W. T., Le��niewski, T., Leniec, G., . . . Liu, R. S. (2022). Broadening Phosphor-Converted Light-Emitting Diode Emission: Controlling Disorder. Chemistry of Materials, 34(22), 10190-10199. doi:10.1021/acs.chemmater.2c03045

Scopus Eid


  • 2-s2.0-85141656881

Start Page


  • 10190

End Page


  • 10199

Volume


  • 34

Issue


  • 22

Place Of Publication


Abstract


  • Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are a highly efficient perspective NIR light source, with application hindered by a narrow emission band. In this work, we broaden the emission of a new series of NIR phosphors by controlling crystal structure disorder through cation cosubstitution. By substituting Ga3+with (Al0.68In0.32)3+, we create a Ga2-x(Al0.68In0.32)xO3:Cr3+phosphor series in which the average crystal size is maintained, while cation disorder varies. The increased deviation of the cation radii in the substitution leads to increased electron-phonon coupling, with a resulting emission spectrum covering the 650-1000 nm range with a 30% increase in the emission full width at half-maximum (FWHM) and a relatively high internal quantum efficiency of ���80%. A transition from the �� phase to the �� phase, which differs in structure from the undoped parent, is created by the application of high pressure and possesses ultra-broad-band emission and an FWHM of ���190 nm. This work shows that the emission bandwidth can be controlled through disorder and its influence on the Stokes shift, as captured by the effective Huang-Rhys factor.

Publication Date


  • 2022

Citation


  • Chang, C. Y., Majewska, N., Chen, K. C., Huang, W. T., Le��niewski, T., Leniec, G., . . . Liu, R. S. (2022). Broadening Phosphor-Converted Light-Emitting Diode Emission: Controlling Disorder. Chemistry of Materials, 34(22), 10190-10199. doi:10.1021/acs.chemmater.2c03045

Scopus Eid


  • 2-s2.0-85141656881

Start Page


  • 10190

End Page


  • 10199

Volume


  • 34

Issue


  • 22

Place Of Publication