Dithioketopyrrolopyrroles (DTPPs) as near-infrared absorbing n-type semiconductors

abstract

English

The diketopyrrolopyrrole derivatives (DPPs) belong to the major organic high-performance pigments finding several significant applications in diverse areas of organic electronics. The core of these derivatives is formed by a molecule with the systematic name 2,5-dihydropyrrolo[4,3-c]pyrrolo-1,4-dione, which offers a wide range of possible structural modifications. One of the important derivatisations is the conversion of oxygen atoms in keto groups to sulfur atoms via one-step thionation using Lawesson’s reagent. In this work, basic thiophenyl (Th-DPP) and phenyl (Ph-DPP) DPP molecules were used as starting materials for the preparation of sulfur analogues Th-DTPP and Ph-DTPP, which were subsequently subjected to a study of electronic structure, optical and semiconducting properties. Thionation brought a bathochromic shift of the solid-state absorption edge. Furthermore, the electronic structure of the studied DTPPs showed low-lying, highly stabilised LUMO orbitals (–4.5 eV), which was in good agreement with model calculations, whereas the experimental HOMO destabilisation was significantly higher than predicted (–5.6 eV). Finally, field effect mobilities were determined on a bottomgate top-contact transistor, where thionation caused the switching of the p-type character of DPPs to the n-type character of DTPPs. Since DTPPs are still sufficiently thermally stable and have nearinfrared absorption capability, low-lying LUMO and n-type mobility, they can be considered potential electron-accepting components in photovoltaics.

diketopyrrolopyrrole; high-performance pigments; thionation; bathochromic shift; n-type; semiconductor

Cigánek, M.; Kratochvíl, M.; Yumusak, C.; Sariciftci, N. S.; Krajčovič, J.

2. 10. 2023

Universitá degli studi di Bari Aldo Moro

Bari, Itálie

978-88-94952-41-4

16th European Conference on Molecular Electronics - ABSTRACT BOOK

112

112

1

https://www.ecme2023.eu/book-of-abstract/