An extended quinoid molecule based on bis(thiophene-diketopyrrolopyrrole) with balanced ambipolar semiconducting properties and strong near-infrared absorption

Abstract

Organic semiconductors that exhibit strong absorption in the near-infrared (NIR) region have received increasing attention as new organic optoelectronic materials. In this paper, we report the synthesis, absorption and semiconducting properties of a new quinoid molecule based on bis(thiophene-diketopyrrolopyrrole) (2DPP-Q-CN) with a long conjugation length. The results reveal that this new quinoid molecule shows strong absorption in the NIR region with a molar extinction coefficient of 380 000 M⁻¹ cm⁻¹. Moreover, the thin film of 2DPP-Q-CN exhibits balanced ambipolar semiconducting properties with hole and electron mobilities up to 0.19 and 0.20 cm² V⁻¹ s⁻¹, respectively.