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Title: para-Azaquinodimethane: A Compact Quinodimethane Variant as an Ambient Stable Building Block for High-Performance Low Band Gap Polymers

Abstract

Quinoidal structures incorporating expanded para-quinodimethane (p-QM) units have garnered great interest as functional organic electronic, optical, and magnetic materials. The direct use of the compact p-QM unit as an electronic building block, however, has been inhibited by the high reactivity conveyed by its biradical character. Herein, we introduce a stable p-QM variant, namely p-azaquinodimethane (p-AQM), that incorporates nitrogen atoms in the central ring and alkoxy substituents on the periphery to increase the stability of the quinoidal structure. The succinct synthesis from readily available precursors leads to regio- and stereospecific p-AQMs that can be readily integrated into the backbone of conjugated polymers. The quinoidal character of the p-AQM unit endows the resulting polymers with narrow band gaps and high carrier transport mobilities. The study of a series of copolymers employing different numbers of thiophene units revealed an unconventional trend in band gaps, which is distinct from the widely adopted donor-acceptor approach to tuning the band gaps of conjugated polymers. Theoretical calculations have shed light on the nature of this trend, which may provide a unique class of conjugated polymers with promising optical and electronic properties.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3];  [2];  [2];  [4];  [4];  [4];  [3];  [2];  [2];  [2];  [2];  [4]; ORCiD logo [2]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); South China Univ. of Technology, Guangzhou (People's Republic of China)
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
  4. South China Univ. of Technology, Guangzhou (People's Republic of China)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1379892
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of the American Chemical Society
Additional Journal Information:
Journal Volume: 139; Journal Issue: 24; Journal ID: ISSN 0002-7863
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Liu, Xuncheng, He, Bo, Anderson, Christopher L., Kang, Jun, Chen, Teresa, Chen, Jinxiang, Feng, Shizhen, Zhang, Lianjie, Kolaczkowski, Matthew A., Teat, Simon J., Brady, Michael A., Zhu, Chenhui, Wang, Lin -Wang, Chen, Junwu, and Liu, Yi. para-Azaquinodimethane: A Compact Quinodimethane Variant as an Ambient Stable Building Block for High-Performance Low Band Gap Polymers. United States: N. p., 2017. Web. doi:10.1021/jacs.7b04031.
Liu, Xuncheng, He, Bo, Anderson, Christopher L., Kang, Jun, Chen, Teresa, Chen, Jinxiang, Feng, Shizhen, Zhang, Lianjie, Kolaczkowski, Matthew A., Teat, Simon J., Brady, Michael A., Zhu, Chenhui, Wang, Lin -Wang, Chen, Junwu, & Liu, Yi. para-Azaquinodimethane: A Compact Quinodimethane Variant as an Ambient Stable Building Block for High-Performance Low Band Gap Polymers. United States. doi:10.1021/jacs.7b04031.
Liu, Xuncheng, He, Bo, Anderson, Christopher L., Kang, Jun, Chen, Teresa, Chen, Jinxiang, Feng, Shizhen, Zhang, Lianjie, Kolaczkowski, Matthew A., Teat, Simon J., Brady, Michael A., Zhu, Chenhui, Wang, Lin -Wang, Chen, Junwu, and Liu, Yi. 2017. "para-Azaquinodimethane: A Compact Quinodimethane Variant as an Ambient Stable Building Block for High-Performance Low Band Gap Polymers". United States. doi:10.1021/jacs.7b04031.
@article{osti_1379892,
title = {para-Azaquinodimethane: A Compact Quinodimethane Variant as an Ambient Stable Building Block for High-Performance Low Band Gap Polymers},
author = {Liu, Xuncheng and He, Bo and Anderson, Christopher L. and Kang, Jun and Chen, Teresa and Chen, Jinxiang and Feng, Shizhen and Zhang, Lianjie and Kolaczkowski, Matthew A. and Teat, Simon J. and Brady, Michael A. and Zhu, Chenhui and Wang, Lin -Wang and Chen, Junwu and Liu, Yi},
abstractNote = {Quinoidal structures incorporating expanded para-quinodimethane (p-QM) units have garnered great interest as functional organic electronic, optical, and magnetic materials. The direct use of the compact p-QM unit as an electronic building block, however, has been inhibited by the high reactivity conveyed by its biradical character. Herein, we introduce a stable p-QM variant, namely p-azaquinodimethane (p-AQM), that incorporates nitrogen atoms in the central ring and alkoxy substituents on the periphery to increase the stability of the quinoidal structure. The succinct synthesis from readily available precursors leads to regio- and stereospecific p-AQMs that can be readily integrated into the backbone of conjugated polymers. The quinoidal character of the p-AQM unit endows the resulting polymers with narrow band gaps and high carrier transport mobilities. The study of a series of copolymers employing different numbers of thiophene units revealed an unconventional trend in band gaps, which is distinct from the widely adopted donor-acceptor approach to tuning the band gaps of conjugated polymers. Theoretical calculations have shed light on the nature of this trend, which may provide a unique class of conjugated polymers with promising optical and electronic properties.},
doi = {10.1021/jacs.7b04031},
journal = {Journal of the American Chemical Society},
number = 24,
volume = 139,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
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