OLED Uygulamaları için Tiyofen-Karbazol Bazlı Donor-Akseptör Polimerler

Öz

Günümüzde organik ışık yayan diyotlar (OLED'ler), düşük maliyet, esneklik, hafiflik ve düşük güç tüketimi gibi benzersiz özellikleri nedeniyle araştırmacılar, bilim insanları ve endüstri adayları tarafından büyük ilgi görmüş ve hayatımıza yenilik getirmiştir. OLED cihaz mimarisinde katmanlar halinde konjuge polimerlerin kullanılması bu teknolojiye büyük avantajlar getirmiş ve ticarileştirilmesine doğru büyük bir adım olmuştur. Bu çalışmada, ana zincirde tiyofen türevleri ve alt birimde kinoksalin köprüsü bulunan karbazol içeren konjuge polimerler tasarlanmıştır. Sentezlenen polimerlerde, ana zincirdeki tiyofen kısmının tiyenotiofen grubu ile değiştirilmesi sonucunda, bant aralığının 2,28 eV'den 2,57 eV'ye daraldığı ve emilim ve emisyon bantlarındaki kayma nedeniyle sarı fotolüminesansın turuncuya dönüştüğü gözlemlenmiştir. Sentezlenen polimer, çeşitli tekniklerle karakterize edildikten sonra, basit çözelti prosesleri ile spin kaplama yöntemi kullanılarak ince filmler hazırlandı ve Organik Işık Yayan Diyotlar (OLED) cihazı ölçümleri yapıldı. Ana zincirde bir floren ve yan grupta farklı uzunluklarda alkil zincirleri olan bir karbazol bileşiği içeren sentezlenmiş tiyofen-karbazol bazlı donör alıcı polimerler (AP1 ve AP2 olarak adlandırılır) polimer bazlı OLED cihazları için kullanılır. OLED cihazları yaklaşık 4 V'da ve 500-700 nm aralığında sarı-yeşil elektrolüminesans yaydı. AP1 OLED cihazının yaklaşık 8 V'da 120 cd/m2 ışık yayarak doygunluğa ulaştığı gözlemlenirken, bu değer AP2 polimeri ile hazırlanan OLED cihazında 85 cd/m2 olarak kaydedildi.

Anahtar Kelimeler

• Tiyofen
• Karbazol
• Donör-Akseptör polimer
• OLED uygulamaları

Thiophene-Carbazole Based Donor-Acceptor Polymers for OLED Application

Öz

Today, organic light emitting diodes (OLEDs) have attracted great interest from researchers, scientists and industry candidates due to their unique features such as low cost, flexibility, light weight and low power consumption and have brought innovation to our lives. The use of conjugated polymers as layers in the OLED device architecture has brought great advantages to this technology and has been a big step towards its commercialization. In this study, conjugated polymers containing thiophene derivatives at the main chain and carbazole exhibited with a quinoxaline bridge in the subunit were designed. In the synthesized polymers, as a result of replacing the thiophene moiety in the main chain with the thienothiophene group, it was observed that the band gap narrowed from 2.28 eV to 2.57 eV and the yellow photoluminescence changed to orange due to the shift in the absorption and emission bands. After the synthesized polymer was characterized with various techniques, thin films were prepared using the spin coating method with simple solution processes and Organic Light Emitting Diodes (OLED) device measurements were performed. Synthesized thiophene-carbazole based donor acceptor polymers (called AP1 and AP2) containing a fluorene in the main chain and a carbazole compound with alkyl chains of different lengths in the side group utilized for polymer-based OLEDs devices. The OLED devices emitted yellow-green electroluminescence at approximately 4 V and in the range of 500-700 nm. The AP1 OLED device was observed to reach saturation by emitting 120 cd/m2 light at around 8 V, while this value was recorded as 85 cd/m2 in the OLED device prepared with AP2 polymer.

Anahtar Kelimeler

• thiophene
• carbazole
• donor acceptor polymer
• OLED applications

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