Selenophene-containing semiconducting polymers for high-performance ambipolar thin film transistor application

Abstract

The development of high-performance and well-balanced ambipolar conjugated polymers are critical to next generation optoelectronic devices. Herein, we report the synthesis and characterization of two APBDOPV polymers containing alternative bis-thiophene, and bis-selenophene as comonomers. The relationship between the structure and opto-electrical property, thin film morphology, molecular packing and solution processing thin film transistors have been investigated systemically. Our results showed that by increasing the size of the chalcogen atom, a stronger red-shifted absorption spectrum, higher IP and a reduced optical band gap are observed for selenophene-containing polymers. The enhanced EA and the planar backbone make both polymers as ambipolar charge transport behaviors under ambient conditions. Particularly, selenophene-containing polymer exhibits much higher and well-balanced hole/electron mobilities up to 0.11/0.15 cm2 V−1 s−1 under ambient conditions with a BGTC device configuration. After further optimization of the TGBC configuration, higher hole/electron mobility of 0.19/0.76 cm2 V−1 s−1 are achieved. Our results also demonstrate that introducing the chalcogen atom into the conjugated backbone is an effective approach to tune the property of the semiconducting polymers.