Two‐Dimensional Conjugated Polymer Synthesized via Interfacial Suzuki Reaction toward Electronic Device Applications

Preparing two-dimensional conjugated polymers (2DCPs) with desirable conjugated structures and semiconducting properties is promising but remains a great challenge. Herein, we present an efficient synthesis of a new 2DCP, named as 2D polytriethyltriindole (2DPTTI) via a modified interfacial Suzuki reaction from 2,7,12-tribromo-5,10,15-triethyltriindole (2-BrTTI) and 1,4-benzenediboronic acid dipinacol ester (BADE) precursors under room temperature. Wafer-scale free-standing 2DPTTI films with controllable thickness of 2.5-46.0 nm were obtained by adjusting the experimental conditions. The resulted 2DPTTI films used as active layer in organic field effect transistors (OFETs) exhibited typical p-type semiconducting electrical transporting property, and superior UV optoelectronic performances with photosensitivity of 3.7 x 10 3 and responsivity of 1.4 x 10 3 A W -1 under 380 nm light irradiation. This result provides a general approach for constructing various semiconducting 2DCPs via interfacial Suzuki reaction toward multi-functional organic optoelectronic applications.