The impact of diperfluorophenyl and thienyl substituents on the electronic structures and charge transport properties of the fused thiophene semiconductors

Abstract

The charge transport properties of 3 fused thiophene semiconductors, end‐capped with diperfluorophenylthien‐2‐yl (DFPT) groups (DFPT‐thieno[2′, 3′:4, 5]thieno[3, 2‐b]thieno[2, 3‐d]thiophene (TTA), DFPT‐dithieno[2, 3‐b:3′, 2′‐d]thiophenes (DTT), and DFPT‐thieno[3, 2‐b]thiophene (TT)), are explored via density functional theory (DFT). To gain a better understanding of the impact of diperfluorophenyl and thienyl substituents on the electronic structures and charge transport properties of these molecules, the geometric structures, reorganization energy, frontier molecular orbitals, molecular ionization potentials and electron affinities, absorption spectra of the corresponding molecules including diperfluorophenyl (DFP)‐TTA, DFP‐DTT, DFP‐TT, dithienyl (DT)‐TTA, DT‐DTT, DT‐TT as well as their parent molecules (TTA, DTT and TT) are investigated for comparison. The calculated results show that introducing perfluorophenyl groups to the fused thiophenes could be a good strategy to promote electron transport, while the insertion of additional thiophene rings to DFP‐end‐capped derivatives could further extend the π‐conjugation and enhance the charge transport properties of DFPT‐end‐capped analogs.

Insight into the semiconducting performance of tetraphenyldipyranylidene derivatives in organic field‐effect transistors

“…Several theoretical models, including band-like transport, hopping transport, and multiple trapping were proposed to find charge transport mechanism in organic semiconductors [27,28]. But the hopping model is the most well-established model that can explain the charge transport mechanism at room temperature for organic semiconductors of OFETs [29].…”

Impact of Furan Substitution on the Optoelectronic Properties of Biphenylyl/Thiophene Derivatives for Light-Emitting Transistors

“…From a structural point of view, rigid planar molecules such as acenes are often considered for semiconducting devices due to their excellent charge carrier transport and mobility. This is due to the fact that the rigidity and planarity give rise to close crystal packing and thus reduce the reorganization energy and improve the charge transfer integrals. − On the other hand, the close packing leads to strong aggregation of transition dipole moments (TDM) in the system, resulting in photoluminescence quenching. Thus, better electrical or optical properties of an organic system is often the trade-off. − However, considering devices like organic light-emitting transistors (OLET) or long-sought organic lasers, high electrical and optical properties are required.…”

Solution Processable Pentafluorophenyl End‐Capped Dithienothiophene Organic Semiconductors for Hole‐Transporting Organic Field Effect Transistors

“…However, the lower solubilities and chemical stabilities of acene-based OSCs critically limited their applications in optoelectronic devices. [21][22] The low stability of acene-based OSCs mainly suffers from oxidation in the presence of light and oxygen. [23] To overcome these disadvantages, fused thiophenes and their derivatives have been widely explored as alternative materials because of their efficient charge carrier transport rising from the planar backbone structure, extensive conjugation, strong π-π stacking/intermolecular interactions in the solid state, and excellent ambient stability.…”

“…[23] To overcome these disadvantages, fused thiophenes and their derivatives have been widely explored as alternative materials because of their efficient charge carrier transport rising from the planar backbone structure, extensive conjugation, strong π-π stacking/intermolecular interactions in the solid state, and excellent ambient stability. [22,[24][25][26][27][28][29][30][31][32] It is anticipated that modification of fused thiophenes will play a vital role in the next-generation organic semiconductors for highperformance and air-stable devices. [25,[33][34][35] As shown in Figures 1 and 2, most of the reported fused thiophene based small molecular organic semiconductors (A, [36] B, [37] D, [38] E, [31] F, [39] G, [40] and N-S [24][25][41][42][43][44] ) have been fabricated via vacuum deposition due to their low solubility.…”