Optical, electrochemical and charge transport properties of fully coplanar diketopyrrolopyrrole thiazole-based semiconductor material

A conjugated semiconductor material with multi-alkyl chains composed of thiazole, thiophene and diketopyrrolopyrrole moieties was designed and synthesized, named PDPP-2T-2Tz. Theoretical simulations confirmed that the molecular structure exhibits excellent coplanarity, which is essential for achieving efficient charge carrier transport. A series of photophysical and electrochemical measurements were conducted to investigate its optical properties and frontier orbital energy levels. Two-dimensional grazing-incidence wide-angle X-ray scattering (2D-GIWAXS) and atomic force microscopy (AFM) results demonstrated the high crystallinity and smooth film morphology of the material. The hole mobility of the annealed film-based transistor materials reached 0.33 cm² V⁻¹ s⁻¹, demonstrating its potential applications for scalable fabrication of flexible circuits.