A diketopyrrolopyrrole containing molecular semiconductor: Synthesis, characterization and solution-processed 1D-microwire based electronic devices

Highly oriented 1D-microwires of a diketopyrrolopyrrole (DPP) based semiconductor i.e. DPP(CBZ)2 (Carbazole capped DPP) were synthesized, characterized and applied to the fabrication of organic optoelectronic devices. 1D-microwires of DPP(CBZ)2 were prepared by solution processing on capillary tubes serving to pin solution. A bottom-gate, top-contact field-effect transistor employing 1D-microwire and polymeric gate dielectric showed a hole mobility of 1.24 × 10−2 cm2/V s, an on-to-off drain current ratio (Ion/Ioff) of 4.7 × 103 and subthreshold slopes of 4 V/dec under ambient conditions. Under white light, a photosensitivity of 800 at VG = −40 V and photoresponsivity of 830 mW/A were achieved. This work demonstrates the potential of this new molecule and the solution method for use in various opto-electronic devices such transistors, photosensors and photovoltaics.

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► Carbazole containing diketopyrrolopyrrole semiconductor was newly synthesized and characterized.
► Highly oriented 1D-microwires of the semiconductor were prepared by solution processing.
► The 1D-microwires based optoelectronic devices’ characteristics were investigated.
► The carbazole moiety contributes the extension of π-conjugation and higher lying HOMO (lowering the oxidation potential).
► The semiconductor provides necessary properties for p-type organic field-effect transistors.