title: Effective Heat Dissipation from Color-Converting Plates in High-Power White Light Emitting Diodes by Transparent Graphene Wrapping.
abstract: We have developed a hybrid phosphor-in-glass plate (PGP) for application in a remote phosphor configuration of high-power white light emitting diodes (WLEDs), in which single-layer graphene was used to modulate the thermal characteristics of the PGP. The degradation of luminescence in the PGP following an increase in temperature could be prevented by applying single-layer graphene. First, it was observed that the emission intensity of the PGP was enhanced by about 20% with graphene wrapping. Notably, the surface temperature of the graphene-wrapped PGP (G-PGP) was found to be higher than that of the bare PGP, implying that the graphene layer effectively acted as a heat dissipation medium on the PGP surface to reduce the thermal quenching of the constituent phosphors. Moreover, these experimental observations were clearly verified through a two-dimensional cellular automata simulation technique and the underlying mechanisms were analyzed. As a result, the proposed G-PGP was found to be efficient in maintaining the luminescence properties of the WLED, and is a promising development in high power WLED applications. This research could be further extended to generate a new class of optical or optoelectronic materials with possible uses in a variety of applications.
authors.forename: Eden
authors.initials: E
authors.lastname: Kim
authors.forename: Hyeon Woo
authors.initials: HW
authors.lastname: Shim
authors.forename: Sanjith
authors.initials: S
authors.lastname: Unithrattil
authors.forename: Yoon Hwa
authors.initials: YH
authors.lastname: Kim
authors.forename: Hojin
authors.initials: H
authors.lastname: Choi
authors.forename: Ki-Jin
authors.initials: KJ
authors.lastname: Ahn
authors.affiliation: Department of Printed Electronics Engineering, Sunchon National University , Jeonnam 57922, South Korea.
authors.forename: Joon Seop
authors.initials: JS
authors.lastname: Kwak
authors.forename: Sungmin
authors.initials: S
authors.lastname: Kim
authors.forename: Hyeonseok
authors.initials: H
authors.lastname: Yoon
authors.forename: Won Bin
authors.initials: WB
authors.lastname: Im
keywords: LEDs; cellular automata; graphene; heat dissipation