Behera Paresh Kumar, Yadav Kajal, Shankar Rao D S, Pandey Upendra Kumar, Sudhakar Achalkumar Ammathnadu
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
Department of Electrical Engineering, School of Engineering, Shiv Nadar Institution of Eminence, Gautam Buddha Nagar, Uttar Pradesh, 201314, India.
Chem Asian J. 2023 May 2;18(9):e202300086. doi: 10.1002/asia.202300086. Epub 2023 Mar 24.
Highly electron-deficient heteroatom (N, S, Se) bay-annulated PBIs exhibiting ordered columnar phase over a wide mesomorphic range including ambient temperature are reported in this manuscript. These compounds with six peripheral n-decyloxy chains exhibited absorption spectra with high molar extinction coefficients, electron-deficient nature and self-assembling behaviour. A detailed comparison with the PBIs bearing six peripheral n-decyl chains was also carried out to get the valuable insights on the structure-property relations in this important class of organic semiconductors. Both of the PBI series were tested for their charge carrier mobility by space charge limited current method and found that they exhibit ambipolar conductivity. This is in contrary to the vast body of literature, where most of the PBI based semiconductors exhibit electron transport behaviour. In general, PBIs derived from tri-n-alkyl anilines exhibit higher mobility values than the PBIs derived from tri-n-alkoxy anilines. Especially, the ambipolar S-annulated PBI derived from tri-n-alkyl aniline exhibited highest hole (8.39×10 cm /V.s) and electron (1.5×10 cm /V.s) mobility values and promising for the application in organic electronics.
本文报道了高度缺电子杂原子（N、S、Se）湾区稠合的聚苯并咪唑（PBIs），其在包括环境温度在内的宽介晶范围内呈现有序柱状相。这些带有六条外围正癸氧基链的化合物表现出具有高摩尔消光系数、缺电子性质和自组装行为的吸收光谱。还对带有六条外围正癸基链的PBIs进行了详细比较，以深入了解这类重要有机半导体的结构-性能关系。通过空间电荷限制电流法对这两个PBI系列的载流子迁移率进行了测试，发现它们表现出双极性导电性。这与大量文献相反，在大多数基于PBI的半导体中表现出电子传输行为。一般来说，由三正烷基苯胺衍生的PBIs比由三正烷氧基苯胺衍生的PBIs表现出更高的迁移率值。特别是，由三正烷基苯胺衍生的双极性S稠合PBI表现出最高的空穴（8.39×10 cm /V.s）和电子（1.5×10 cm /V.s）迁移率值，有望应用于有机电子学领域。
