Hydrogen-Bonded Organic Semiconductors with Long Charge Carrier Lifetimes

Abstract

Hydrogen bonds are noncovalent interactions able to improve the electronic properties of self-assembled semiconductors. Nevertheless, it is necessary to control the parameters influencing the formation of hydrogen bonds to achieve hierarchical structures with enhanced properties. In this work, we explore two hydrogen-bonded thiophene-capped diketopyrrolopyrrole (DPP) derivatives containing amides with different topology (C- or N-centered) and compare them to a control analogue without hydrogen bonds. We demonstrate the differences in the optoelectronic and self-assembly properties of the two amide-containing DPP derivatives, as well as in their charge carrier lifetimes. We prove the superior properties of the hydrogen-bonded derivatives in comparison to the control molecule without hydrogen bonds, and show that our molecular design strategy results in supramolecular structures with particularly long charge carrier lifetimes compared to other amide-containing semiconductors reported in the literature.

Self‐assembly of chiral diketopyrrolopyrrole chromophores giving supramolecular chains in monolayers and twisted microtapes

“…Future design of materials could look to increase conjugation while retaining the favorable optoelectronic and self‐assembly properties of the subjects of this article or their use as a morphological additive through a sergeants and soldiers' chiral induction approach 141 to dictate morphology of state‐of‐the‐art donors. Ultimately, this may lead to organic semiconductors with long charge carrier lifetimes 142 . The DPPs are particularly promising in this regard 143 .…”

Unsubstituted thiophene–diketopyrrolopyrrole conjugated polymer thin films via oxidative chemical vapor deposition – electronic behavior

“…66 The longevity of charge signatures facilitated through enhanced hydrogen bonds is in accord with the results by Ávila-Rovelo et al in thiophene-capped DPP molecules. 52…”

“…66 The longevity of charge signatures facilitated through enhanced hydrogen bonds is in accord with the results by A ´vila-Rovelo et al in thiophene-capped DPP molecules. 52 The ability to synthesize N-unsubstituted thiophene-diketopyrrolopyrrole conjugated polymers and readily deposit them in the form smooth, dense and thickness-controlled thin films constitutes a breakthrough in the field of DPP-based conjugated polymers. Particularly, the simplicity of the proposed CVD method contrasts with recently developed solution-based approach towards the synthesis of DPP-based blue-colored pigments, which involves (i) tetrahydrofuran, chloroform, and toluene as solvents, (ii) di-tert-butyl decarbonate, N-bromosuccinimide and tetrakis(triphenylphosphine) palladium for grafting boc groups and enabling the Stille coupling, and (iii) a thermal treatment (190 1C) in the presence trifluoromethylsulfonic acid to ensure a complete removal of the boc group.…”

“…Indeed, vibronic and electronic coupling is influenced by the molecular structure, and p-p stacking can induce a photocurrent enhancement. 34,35,[48][49][50][51][52][53]…”

Alternative Functionalization of Hydrogen‐Bonded Diketopyrrolopyrrole Derivatives**

“…These materials have gained attention since the ordered supramolecular structures can improve charge transport and reduce exciton recombination losses in organic electronic devices. [1] They can be synthesized by introducing functional groups that can participate in hydrogen bonding, such as amides and ureas, into the molecular structure of traditional organic semiconductors. [2,3] The ability to tune the properties of these materials through hydrogen-bonding has led to the development of optoelectronic devices.…”