Summary

エキシプレックスからの安定した発光と白色発光電気化学セルの作製

Published: November 15, 2016
doi:

Summary

The authors present a method for fabricating stable white-light-emitting electrochemical cells utilizing emission from exciplexes formed between a blue-emitting fluorene polymer and aromatic amines.

Abstract

著者らは、(青色蛍光ポリ(9,9-ジ-n- dodecylfluorenyl -2,7-ジイル)からなる活性層を有する高分子発光電気化学セルからの安定した白色発光(PLECS)を製造するための方法を提供しますPFD)とπ共役トリフェニルアミン分子。この白色発光は、電子的に励起状態にPFDおよびアミンとの間に形成された励起錯体に由来します。 PFD、4,4 '、4 "を含むデバイス" -トリス[2-ナフチル(フェニル)アミノ]トリフェニルアミン(2-TNATA)、ポリ(エチレンオキシド)及びK 2 CF 3 SO 3委員会国際と白色発光を示しました。ドゥéclairage(CIE)(0.33、0.43)の座標と3.5Vで定電圧測定の印加電圧でのRa = 73の演色指数(CRI)は(0.27、0.37)のCIE座標ことが示された、Raは67、および5Vの電圧を印加した直後に観察された発光色はほぼ変わらないと後に安定であったの300秒。

Introduction

Research and development of polymer light-emitting electrochemical cells (PLECs) have expanded in recent years.1-15 PLECs are similar to organic light-emitting diodes (OLEDs) in that both are surface emitting organic devices and are expected to find their way into future lighting applications. OLEDs are already on the market, but the cost is still high, one reason being that OLEDs need a complicated device structure with multiple layers. In contrast, PLECs have a very simple device structure which consists of a single active layer (emitting layer) between a pair of electrodes. This means that PLECs are suited to mass production processes such as roll-to-roll printing and coating.

A PLEC has an active layer consisting of a fluorescent π-conjugated polymer (FCP). The FCP can be electrochemically doped with a polymer electrolyte (a mixture of an ion conducting polymer and a salt). The FCP is p-doped on the anode side and n-doped on the cathode side during operation, and generates excitons which emit light between the p- and n-doped regions. Therefore, the emission color reflects the exciton emission (=fluorescence) wavelength of the FCP.

Stable white light emission is important for lighting applications, and color mixing techniques which employ two or more emitters have been widely used to achieve this.10-14 Recently, we presented a different approach for obtaining stable white light emission, using an active layer which contains blue-fluorescent poly(9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) and π-conjugated aromatic amines15. This white light emission comes from exciplexes formed between PFD and amine molecules in excited states. Exciplex emission has a broader spectrum compared to the exciton emission from the PDF and/or amines, which gives it a color close to that of natural light. This translates to a higher color rendering index (CRI), which is preferable for lighting applications.

In this article, the authors describe the procedure used to fabricate the exciplex based LECs and show the stability of their white light emission.

Protocol

活性層ソリューションの調製 アミンドープPFDデバイス用のアクティブ層溶液 注:PFD、4,4 '、4' ' -トリス[2-ナフチル(フェニル)アミノ]トリフェニルアミン(2-TNATA)、9,9-ジメチルN、N'-ジ(1-ナフチル) – N 、N 'ジフェニル- 9Hフルオレン-2,7-ジアミン(DMFL-NPB)受信した、ポリ(エチレンオキシド)(PEO)を使用しました。トリフルオロメタ…

Representative Results

エレクトロルミネッセンス(EL)スペクトルは、CIE座標およびCRI値( 図2、図4、図5)を計算するために使用しました。発光素子の写真画像は、発光( 図3)の白色度を確認するために収集しました。 アミンドープPFD装置とアンドープPFD装置のELスペクトルを図2に示されている。アンド…

Discussion

LECは、疎水性PFD及び芳香族アミンを含む活性層、及び親水性ポリエチレンオキシドおよびKCF 3 SO 3を有します。これらの材料は非常に異なる溶解度を有するので、スピンコーティング溶液の入念な準備が不完全な溶媒和を避けるために重要です。まず各別々に溶解されなければならず、完全に十分な溶媒和能力を有する溶媒中で、次に溶液は、均一な混合物を形成するために?…

Disclosures

The authors have nothing to disclose.

Acknowledgements

この作品は、部分的に科学研究費補助金(第24225003)によってサポートされていました。この作品は、JX日鉱日石エネルギー株式会社によって財政的にサポートされていました。

Materials

Poly(9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) Aldrich 571660
4,4’,4’’-Tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA) Aldrich 768669
9,9-Dimethyl-N,N’-di(1-naphthyl)-N,N’-diphenyl-9H-fluorene-2,7-diamine (DMFL-NPB) Aldrich
Poly(ethylene oxide) (PEO) Aldrich 182028
Potassium tirifluoromethansulfonate (KCF3SO3) Aldrich 422843 dried under vacuum at 200 °C for 2 hr prior to use
Chloroform Kanto Chemical Co. 08097-25 dehydrated
Cyclohexanone Kanto Chemical Co. 07555-00
SCAT 20-X (detergent) Daiichi Kogyo Seiyaku diluted with water
Acetone Kanto Chemical Co. 01866-25 Electronic grage
2-propanol Kanto Chemical Co. 32439-75 Electronic grage
13mm GD/X Disposable Filter Device PVDF Filter Media, Polypropylene Housing Whatman 6872-1304
UV/O3 Treating Unit SEN Lights Co.  SSP16-110
Spectral Photo Detector Otsuka Electronics MCPD 9800
Voltage Current Source Monitor  ADCMT 6241A 
Evaporation Mask  Tokyo Process Service Co., Ltd. NA The evaporation mask was wet-etched to create openings for patterned deposition of aluminum. The size of the mask is 100 mm x 100 mm x 0.2 mm-thick.

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Cite This Article
Uchida, S., Takizawa, D., Ikeda, S., Takeuchi, H., Nishimura, S., Nishide, H., Nishikitani, Y. Fabrication of White Light-emitting Electrochemical Cells with Stable Emission from Exciplexes. J. Vis. Exp. (117), e54628, doi:10.3791/54628 (2016).

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