白的制造发光电化学细胞与来自激发络合物稳定的发射
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
作者提出的用于制造由高分子发光电化学电池具有其由蓝色荧光的聚（9,9-二正dodecylfluorenyl -2,7-二基）的活性层稳定的白光发射（PLECS）的方法（ PFD）和π共轭三苯基胺的分子。这种白光发射从电子激发态PFD和胺之间形成激发络合物起源。含有PFD，4,4'，4''装置-三[2-萘基（苯基）氨基]三苯基胺（2-TNATA），聚（环氧乙烷）和K 2 CF 3 SO 3显示白色发光用委员会国际歌DE L'éclairage（CIE）坐标的（0.33，0.43）和以3.5 V恒定电压测量的施加电压为Ra = 73的显色指数（CRI）表明，在CIE的（0.27，0.37）中，Ra的坐标67，及5V的施加电压后立即观察到的发光颜色几乎不变，后稳定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
Representative Results
Discussion
该LEC具有包含疏水PFD和芳族胺，和亲水聚环氧乙烷和KCF 3 SO 3的有源层。因为这些材料具有非常不同的溶解度，旋涂溶液的精心准备是关键的，以避免不完全溶解。每个必须首先在有足够的溶解能力的，则该溶液被混合在一起以形成均匀的混合物的溶剂分别和完全溶解。平衡激子和激基复合物的排放量是关键，获得白光发射。因此，PFD和胺的量必须精确测量。
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Divulgazioni
The authors have nothing to disclose.
Acknowledgements
这项工作是部分被格兰特 – 在援助科学研究（24225003号）的支持。这项工作是由JX新日本石油和能源公司资助。
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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