| Abstract [eng] |
In this work, eight compounds containing electron‐withdrawing fragments of xanthenone and thioxanthenone were synthesized and investigated, which were subsequently applied in the formation of organic light emitting diodes. Four different donor substituents were attached to the xanthenone and thioxanthenone fragments by Buchwald-Hartwig method using 10H-phenoxazine, 3,6-di-tert- butyl-carbazole, 3,7-di-tert-butyl-phenothiazine and 2,7-di-tert-butyl-9,9-dimethyl-9,10- dihydroacridine to give new bipolar materials. The obtained compounds were investigated to have relatively high thermal stability with 5% weigh loss temperatures reaching 366 oC and high glass transition temperatures reaching 116 oC. Investigation of photophysical properties showed that the synthesized compounds exhibit thermally activated delayed fluorescence and aggregation induced emission enhancement. The characterized and investigated materials were used as emitters in the fabrication of organic light emitting diodes. Devices containing 2-(2,7-di-tert-butyl-9,9- dimethylacridin-10(9H)-yl)-9H-thioxanten-9-one showed a maximum external quantum efficiency of 8.24%. |
