Fabrication de lumière blanche émettant des cellules électrochimiques avec des émissions de Stable exciplexes
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
Les auteurs présentent une approche de fabrication stable blanc émission de lumière à partir de cellules électrochimiques polymère émettrices de lumière (Plecs) ayant une couche active qui consiste en poly bleu fluorescent (9,9-di-n-dodecylfluorenyl-2,7-diyl) ( PFD) et des molécules de triphénylamine π-conjugués. Cette émission de lumière blanche provient de exciplexes formés entre PFD et amines dans les états électroniques excités. Dispositif contenant VFI, 4,4 ', 4' '- tris [2-naphtyle (phényl) amino] triphénylamine (2-TNATA), le poly (oxyde d'éthylène) , et K 2 CF 3 SO 3 montre émission de lumière blanche avec la Commission internationale de l'éclairage (CIE) coordonne de (0,33, 0,43) et un indice de rendu des couleurs (IRC) de Ra = 73 à une tension appliquée de 3,5 V. les mesures de tension constante a montré que la CIE coordonne de (0,27, 0,37), Ra de 67 ans, et la couleur d'émission observée immédiatement après l'application d'une tension de 5 V étaient pratiquement inchangés et stables après300 s.
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
Le LEC possède une couche active contenant VFI hydrophobe et d' amines aromatiques, et hydrophiles d' oxyde de polyéthylène et le KCF 3 SO 3. Parce que ces matériaux ont des solubilités très différentes, une préparation minutieuse de la solution de revêtement par centrifugation est essentiel pour éviter la solvatation incomplète. Chacun doit être d'abord dissous séparément et complètement dans les solvants avec la capacité de solvatation suffisante, les solutions sont m?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
Ce travail a été partiellement financé par une subvention en aide pour la recherche scientifique (n ° 24225003). Ce travail a été soutenu financièrement par le Oil & Energy Corporation JX Nippon.
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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