A novel, soluble, and strong electron withdrawing polyimide (PI), and its first use to modulate photoelectrical characteristics of organic thin film phototransistors (OPTs), are reported. The PI with strong electron‐withdrawing repeating units is solution blended with UV‐responsive organic semiconductor 2,7‐dipentyl[1]benzothieno[3,2‐b][1]benzothiophene (C5‐BTBT). Photoelectrical properties of OPTs are affected by content but not molecular weight of PI in the blends, which is attributed to strong charge trapping at the interface. 10 wt% PI only in the blends can completely suppress the hysteresis under UV light and increase the drain photocurrent by more than six orders of magnitude in the subthreshold region. All the blend‐based OPTs show excellent operational stability in air and high sensitivity to UV light at a low intensity (0.12 mW cm⁻²). I_phc/I_D and photosensitivity were 10⁶ and 429 A W⁻¹, respectively, for 70:30 PI1:C5‐BTBT blend. All the blend‐based OPTs have response times of ≈1 s and decay times (UV off) of 149 s, which are 16 times faster and 2 times slower than the control C5‐BTBT OPT. Density functional theory calculations is used to understand the mechanisms. This work demonstrates that the PI/C5‐BTBT blends represent a very promising system for high‐performance OPT devices.

中文翻译：

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聚酰亚胺和苯并噻吩并苯并噻吩的二元共混物，用于高性能溶液加工的有机光电晶体管

报道了一种新颖的，可溶的和强吸电子的聚酰亚胺（PI），其首次用于调节有机薄膜光电晶体管（OPT）的光电特性。将具有强吸电子重复单元的PI与紫外线响应有机半导体2,7-二戊基[1]苯并噻吩并[3,2-b] [1]苯并噻吩（C5-BTBT）溶液共混。OPT的光电性能受掺合物中PI的含量的影响，但不受其分子量的影响，这归因于界面处的强电荷俘获。仅共混物中的10 wt％PI可以完全抑制UV光下的磁滞现象，并在亚阈值区域中将漏极光电流增加超过六个数量级。所有基于共混物的OPT在空气中表现出出色的操作稳定性，并且在低强度（0.12 mW cm）下对紫外线具有高灵敏度^-2）。对于70:30 PI1：C5-BTBT混合物，I _phc / I _D和光敏性分别为10 ⁶和429 AW ^-1。所有基于混合的OPT的响应时间均为≈1s，衰减时间（UV关闭）为149 s，这比对照C5-BTBT OPT快16倍，慢2倍。密度泛函理论计算用于理解机理。这项工作表明，PI / C5-BTBT混合物代表了用于高性能OPT设备的非常有前途的系统。