Halogenated Tetraazapentacenes with Electron Mobility as High as 27.8 cm2 V−1 s−1 in Solution‐Processed n‐Channel Organic Thin‐Film Transistors. Issue 38 (31st July 2018)

• Record Type: Journal Article
• Authors: Chu, Ming; Fan, Jian‐Xun; Yang, Shuaijun; Liu, Dan; Ng, Chun Fai; Dong, Huanli; Ren, Ai‐Min; Miao, Qian
• Is Part Of: Advanced materials. Volume 30:Issue 38(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-07-31
• Subjects: charge transport -- electron mobility -- organic field‐effect transistors -- organic semiconductors; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201803467
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Molecular engineering of tetraazapentacene with different numbers of fluorine and chlorine substituents fine‐tunes the frontier molecular orbitals, molecular vibrations, and π–π stacking for n‐type organic semiconductors. Among the six halogenated tetraazapentacenes studied herein, the tetrachloro derivative (4Cl‐TAP) in solution‐processed thin‐film transistors exhibits electron mobility of 14.9 ± 4.9 cm 2 V −1 s −1 with a maximum value of 27.8 cm 2 V −1 s −1, which sets a new record for n‐channel organic field‐effect transistors. Computational studies on the basis of crystal structures shed light on the structure–property relationships for organic semiconductors. First, chlorine substituents slightly decrease the reorganization energy of the tetraazapentacene whereas fluorine substituents increase the reorganization energy as a result of fine‐tuning molecular vibrations. Second, the electron transfer integral is very sensitive to subtle changes in the 2D π‐stacking with brickwork arrangement. The unprecedentedly high electron mobility of 4Cl‐TAP is attributed to the reduced reorganization energy and enhanced electron transfer integral as a result of modification of tetraazapentacene with four chlorine substituents. Abstract : Molecular engineering of tetraazapentacene with different numbers of fluorine and chlorine substituents fine‐tunes the frontier molecular orbitals, molecular vibrations, and π–π stacking for n‐type organic semiconductors. The tetrachloro derivative in solution‐processed thin‐film transistors exhibit electron mobility of 14.9 ± 4.9 cm 2 V −1 s −1 with a maximum value of 27.8 cm 2 V −1 s −1, which sets a new record for n‐channel organic field‐effect transistors.