Synteza niektórych azotowych układów heterocyklicznych i ich zastosowanie w komórkach elektroluminescencyjnych
AbstractThis project focused on the synthesis of some nitrogen heterocycles and their practical applications in organic electronics. The synthesised compounds belonged to derivatives of 1H-pyrazolo[3,4-1,]quinolines (PQ), 1H-pyrazolo[3,4-b]quinoxalines (PQX), bispyrazolo[3,4-b;4',3'-e]pyridines (BPP), benzoxazoles (BOX) and 1,3,4-oxadiazoles (OXD). Novel syntheses of PQ and PQX have been proposed and proven. Pyrazoloquinolines could be prepared in a one-step procedure from cheap commercially available starting materials. Thus, the synthesis is one of the best procedures ever described. The materials prepared emitted strong light both in solutions and in the solid state. Predominantly, the blue emission was observed. After some structural modifications, green luminophores became available. The electroluminescent devices were constructed involving either the vacuum evaporation technology or doping luminophores into polymer matrices. In the first case, multilayer cells with hole transport layer/emitting layer/electron transport layer configuration were fabricated. Single- and multilayer devices emitting either bright blue, blue-green or green light with luminance in the range of 3000 to 37 000 cd/rn2 were produced with these materials. The majority of PQ and some BPP applied in electroluminescent devices fulfilled the requirements of Commission Internationale de l'Eclairage for blue pixel CIEx,y coordinates (0.14-0.16; 0.11-0.15). There is a strong demand for thermally stable and amorphous organic materials for organic light-emitting devices. In this study, these properties of luminophores were met by replacement of commonly employed spirobifluorene moiety with the spirobiindane core. Spirobiindane (SBI) derivatives could be prepared in a one-step process starting from commercially available bisphenol A, a cheap starting material for polymer synthesis. The spirobiindane moiety offered a high thermal stability of the materials. They decomposed between 490 and 500 °C. The glass transition temperature of such compounds was 2-3 times higher than that recorded for materials without the Spiro moieties. SBI could be a cheap starting material for the synthesis of hole-transporting, electron-transporting and emissive materials. Apart from spirobiindane-based structures also some PQ dimers were synthesised from derivatives of bisphenol A and fluorene. The synthesis of copolymers with 9-vinylcarbazole also employed PQ. The polymers providing smooth, pinhole-free films, were applied in construction of single-layer electroluminescent devices. Besides of it, poly(9-vinylcarbazole) provided a matrix for PQ and BPP dopants in single-layer devices of the ITO/PEDOT/polymer/Ca/Al configuration. The electroluminescent devices constructed in this study emitted blue light with Lmax, ranging from 70 to 4000 cd/m2.
|Other language title versions||Synthesis of some nitrogen heterocycles and their application in electroluminescent devices|
|Publisher||Uniwersytet Rolniczy im. Hugona Kołłątaja w Krakowie, MNiSW |
|Publishing place (Publisher address)||Kraków|
|Book series /Journal (in case of Journal special issue)||Zeszyty Naukowe Uniwersytetu Rolniczego im. Hugona Kołłątaja w Krakowie. Rozprawy, ISSN 1899-3486, (0 pkt)|
|Publication size in sheets||12|
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