诺中环扩张的效应 有机场效应晶体管中的诺聚合物
Hu Chen1, Andrew Wadsworth2, Chun Ma1
1King Abdullah University of Science and Technology (KAUST) , KAUST Solar Center (KSC) , Thuwal 23955-6900 , Saudi Arabia.
Journal of the American Chemical Society
|October 16, 2019
概括
合成了一种新的化供体 - - 丁二二烯 (TBIDT),但导致电荷载体的移动性低于预期. 这凸显了高性能有机场效应晶体管的正规侧链包装的重要性.
科学领域:
- 有机电子产品
- 材料科学
- 聚合物化学
背景情况:
- 已知伊达二 (IDT) 单元可增强有机半导体中的电荷载体流动性.
- 将IDT单元扩展为丁[b]丁烯 (TBIDT) 被假设为进一步提高聚合物平面性和分子间接触.
研究的目的:
- 设计和合成一种新型的化供体,TBIDT,并将其与甲 (BT) 共聚合.
- 调查扩展TBIDT单元对生成的聚合物的微结构和电荷传输特性的影响 (TBIDT-BT).
- 了解有机半导体中电荷载体移动性的结构属性关系.
主要方法:
- 通过酸促级联环闭合合成TBIDT单体.
- TBIDT与BT单体的共聚化
- 有机场效应晶体管 (OFET) 的制造和表征.
- 时间分辨率微波导电性 (TRMC) 测量.
- 扫描道显微镜 (STM) 和密度功能理论 (DFT) 的计算.
主要成果:
- 与IDT-BT相比,优化的TBIDT-BT场效应晶体管显示出较低的平均和孔移动性 (0.9cm^2V^-1s^-1). 这样一来,
- TRMC测量证实了OFET设备中观察到的下方孔的移动性.
- STM和DFT发现TBIDT-BT的微观结构比IDT-BT少,这是由于不规则的侧链包装.
- 由于较弱的静电相互作用,DFT计算表明TBIDT-BT平面骨干几何的稳定性降低.
结论:
- 正常的侧链封装密度对于有机半导体的高电荷载体移动性至关重要,因为不规则的封装可以创建陷点.
- 尽管TBIDT-BT具有较大的平面融合单元,但由于背骨平面稳定性和微观结构较差,其电荷传输性能较差.
- 这些发现强调了考虑分子间相互作用和包装的重要性 ஒழுங்கு (规律性) 在设计具有扩展化骨架的高性能半导体聚合物时.
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