高演色性螢光粉調控及其於發光二極體之應用

Control of High Color Rendition Phosphors and Their Application in White Light-Emitting Diodes

方牧懷(Mu-Huai Fang)

指導教授 ： 劉如熹

國立臺灣大學/理學院/化學研究所/博士(2018年)

https://doi.org/10.6342/NTU201800981

摘要

無資料

關鍵字

螢光粉 ； 發光二極體

並列摘要

Manufacturing high-quality luminescent devices with low color temperature, high color rendering index and high luminous efficacy (LE) has become an urgent challenge worldwide. Phosphor materials used in light-emitting diodes (LEDs) have thus attracted much research attention. There are two important factors to tune the photoluminescence spectrum and build up high quality LED devices. First, is to discover the narrow-band emission red phosphors. The narrow-emission red component can not only increase the color rendition of the LED device but also suppress the spillover of the photons longer than 650 nm, which is insensitive to the human eye. Second, is to develop the cyan phosphor in 480–520 nm region. The cyan phosphor can improve the color vividness, decrease the color distortion, and obtain real full-spectrum lighting.
For the first section, we will focus on the Mn4+-doped fluoride phosphors and Eu2+-doped nitride phosphors. In this study, a new Rb2SiF6:Mn4+ phosphor was synthesized through a simple co-precipitation method, which can help obtain the pure phase of the fluoride phosphors. Besides, KNaSiF6:Mn4+ was synthesized via a two-step co-precipitation method. The intermediate phase of KNaSiF6:Mn4+ showed different structures and luminescent properties, especially in terms of zero-phonon line (ZPL) intensity, from K2SiF6:Mn4+ and Na2SiF6:Mn4+. This study aims to elucidate the mechanism of the ZPL intensity in AMF6:Mn4+ (A = Na, K, Cs, Ba, Rb; M = Si, Ti, and Ge).
Moreover, a series of Eu2+-doped SrLiAl3N4 (SLA) phosphors are synthesized using gas pressure sintering (GPS) and hot isostatic press (HIP) systems. The results can help understand the pressure effect of the solid-state reaction. To tune the crystal structure of SLA, a series of Sr(Li1-xSix)(Al1-xMgx)3N4:Eu2+ phosphors were synthesized by HIP, which emission wavelength shifts toward longer wavelength and then shifts to a shorter wavelength. This research can not only help the researchers understand the unexpected properties during the solid-solution process but also provide an insight of the analysis methods.
For the second section, a series of Sr4.7−xBaxEu0.3(PO4)3Cl cyan phosphor was synthesized by a solid-state method in the tube furnace. The structure and luminescence properties of Sr4.7−xBaxEu0.3(PO4)3Cl are examined in detail. We also propose a mechanism for the unique behavior of tuning the photoluminescence spectra. Finally, LED devices are constructed to show the practical properties of the phosphors.

並列關鍵字

Phosphor ； Light-Emitting Diodes

參考文獻

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