High Charge Carrier Mobility, Low Band Gap Donor–Acceptor Benzothiadiazole-oligothiophene Based Polymeric Semiconductors
作者:Boyi Fu、Jose Baltazar、Zhaokang Hu、An-Ting Chien、Satish Kumar、Clifford L. Henderson、David M. Collard、Elsa Reichmanis
DOI:10.1021/cm3021929
日期:2012.11.13
Spin-coated films of the poly(benzothiadiazole-sexithiophene) PBT6, which exhibits a highly crystalline lamellar π–π stacked edge-on orientation on the OFET substrate, possesses a hole mobility of ca. 0.2 cm2/V·s. Vinylene-containing analogs PBT6V2 and PBT6V2′ are amorphous and exhibit very low mobilities. The molecular weight of PBT6 has a strong influence on the electronic properties: a sample with
合成并表征了一系列苯并噻二唑低聚噻吩和低聚(亚噻吩乙烯撑)供体-受体(DA)共聚物。这些低光学带隙材料(〜1.5 eV)能够吸收400–800 nm范围内的光子,并具有良好的热稳定性。使用有机场效应晶体管(OFET)结构确定的空穴迁移率在3个数量级的范围内变化,并且与各个薄膜的分子有序性和形态密切相关。聚(苯并噻二唑-噻吩并噻吩)PBT6的旋涂膜在OFET衬底上呈现出高度结晶的层状π-π堆叠边沿取向,其空穴迁移率约为ca。0.2 cm 2 / V·s。含乙烯的类似物PBT6V2PBT6V2'和PBT6V2'是无定形的,并且显示出非常低的迁移率。PBT6的分子量对电子性能有很大的影响:分子量较低的样品的迁移率比高分子量的同系物低约1个数量级,并且最大吸收值明显偏蓝移。PBT6的空穴迁移率进一步提高了约两倍。图3通过滴铸法制造OFET。用这种方法制造的OFETs的迁移率高达0.75 cm 2 /