Diacenopentalene dicarboximides as new n-type organic semiconductors for field-effect transistors

Fang

Chemistry An Asian Journal

et al. 2018

It is very important to develop ambipolar field effect transistors to construct complementary circuits. To obtain balanced hole- and electron-transport properties, one of the key issues is to regulate the energy levels of the frontier orbitals of the semiconductor materials by structural tailoring, so that they match well with the electrode Fermi levels. Five conjugated copolymers were synthesized and exhibited low LUMO energy levels and narrow bandgaps on account of the strong electron-withdrawing effect of the carbonyl groups. Polymer thin film transistors were prepared by using a solution method and exhibited high and balanced hole and electron mobility of up to 0.46 cm V s , which suggested that these copolymers are promising ambipolar semiconductor materials.

Section: Resultsmentioning

confidence: 99%

Solution‐Processable Balanced Ambipolar Field‐Effect Transistors Based on Carbonyl‐Regulated Copolymers

Fang

Chemistry An Asian Journal

et al. 2018

“…Bisimide is another well‐known soluble moiety with electron withdrawing functionality. Various acene and rylene bisimides have been reported to be good p‐, n‐, or ambipolar semiconductors. In the TTF family, only n ‐butyl‐ and n ‐hexyl‐substituted dibenzo TTF bisimide ( C4‐ and C6‐DBTTF‐Im ) have been proposed for use as air‐stable p‐type materials (Figure ).…”

Section: Figurementioning

confidence: 99%

Dinaphthotetrathiafulvalene Bisimides: A New Member of the Family of π‐Extended TTF Stable p‐Type Semiconductors

Yamashita

Kawano

Matsumoto

et al. 2017

Chemistry A European J

Air-stable organic semiconductors based on tetrathiafuluvalene (TTF) were developed by synthesising a series of dinaphthotetrathiafulvalene bisimides (DNTTF-Im) using electron-donating TTF, π-extended naphthalene, and electron-withdrawing imide. Electron-spin-resonance spectroscopy and X-ray single-crystal structure analysis of aryl-substituted DNTTF-Im radical cations confirmed that localisation of the spin resides on the electron-donating TTF moiety. The organic field-effect transistor properties derived from the use of highly crystalline n-butyl (C4) and n-hexyl(C6)-substituted DNTTF-Im were assessed. The hole carrier mobility of C6-DNTTF-Im was improved from 3.7×10 cm V s to 0.30 cm V s in ambient conditions. This is attributed to the raise of the substrate temperature from 25 °C to 200 °C during sublimation. The XRD and microscopy analysis suggested that increasing the substrate temperature accelerates the end-on packing resulting in larger grains suitable for hole charge transport parallel to the substrate.

“…[23] The oxidation and reduction products of DBP are also of interest regarding the application of DBPs as semiconductors in organic field-effectt ransistors (OFETs). DBP derivatives and further benzannulated diaceno[a,e]pentalenes have been employed in both p- [24][25][26][27][28][29] and n-type [30] OFET devices. The charge transport is thought to proceed throughe ither the cation radical in the case of p-type doping or the anion radicalf or an ntype device.…”

Section: Introductionmentioning

confidence: 99%

Cations and Anions of Dibenzo[a,e]pentalene and Reduction of a Dibenzo[a,e]pentalenophane

Hermann

Böttcher

Schorpp

et al. 2021

Chemistry A European J

Dibenzo[a,e]pentalene (DBP) is a non‐alternant conjugated hydrocarbon with antiaromatic character and ambipolar electrochemical behavior. Upon both reduction and oxidation, it becomes aromatic. We herein study the chemical oxidation and reduction of a planar DBP derivative and a bent DBP‐phane. The molecular structures of its planar dication, cation radical and anion radical in the solid state demonstrate the gained aromaticity through bond length equalization, which is supported by nucleus independent chemical shift‐calculations. EPR spectra on the cation radical confirm the spin delocalization over the DBP framework. A similar delocalization was not possible in the reduced bent DBP‐phane, which stabilized itself by proton abstraction from a solvent molecule upon reduction. This is the first report on structures of a DBP cation radical and dication in the solid state and of a reduced bent DBP derivative. Our study provides valuable insight into the charged species of DBP for its application as semiconductor.