Nonplanar Rhombus and Kagome 2D Covalent Organic Frameworks from Distorted Aromatics for Electrical Conduction

Guolong Xing; Wenhao Zheng; Lei Gao; Ting Zhang; Xiaowei Wu; Shuai Fu; Xiaoyu Song; Ziqiang Zhao; Silvio Osella; Marta Martínez-Abadía; Hai I Wang; Jinming Cai; Aurelio Mateo-Alonso; Long Chen

doi:10.1021/jacs.1c13534

Nonplanar Rhombus and Kagome 2D Covalent Organic Frameworks from Distorted Aromatics for Electrical Conduction

J Am Chem Soc. 2022 Mar 23;144(11):5042-5050. doi: 10.1021/jacs.1c13534. Epub 2022 Feb 21.

Authors

Guolong Xing^{1

2}, Wenhao Zheng³, Lei Gao⁴, Ting Zhang^{1

2}, Xiaowei Wu⁵, Shuai Fu³, Xiaoyu Song², Ziqiang Zhao^{1

2}, Silvio Osella⁶, Marta Martínez-Abadía⁷, Hai I Wang³, Jinming Cai⁴, Aurelio Mateo-Alonso^{7

8}, Long Chen^{1

2}

Affiliations

¹ State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
² Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin 300072, China.
³ Max Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany.
⁴ Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China.
⁵ Fujian Institute of Research on the Structure of Matter, Xiamen Institute of Rare Earth Materials, Chinese Academy of Sciences, Xiamen 361021, China.
⁶ Chemical and Biological Systems Simulation Lab, Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland.
⁷ POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain.
⁸ Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain.

PMID: 35189061
DOI: 10.1021/jacs.1c13534

Abstract

Two-dimensional (2D) covalent organic frameworks (COFs) are an emerging class of promising 2D materials with high crystallinity and tunable structures. However, the low electrical conductivity impedes their applications in electronics and optoelectronics. Integrating large π-conjugated building blocks into 2D lattices to enhance efficient π-stacking and chemical doping is an effective way to improve the conductivity of 2D COFs. Herein, two nonplanar 2D COFs with kagome (DHP-COF) and rhombus (c-HBC-COF) lattices have been designed and synthesized from distorted aromatics with different π-conjugated structures (flexible and rigid structure, respectively). DHP-COF shows a highly distorted 2D lattice that hampers stacking, consequently limiting its charge carrier transport properties. Conversely, c-HBC-COF, with distorted although concave-convex self-complementary nodes, shows a less distorted 2D lattice that does not interfere with interlayer π-stacking. Employing time- and frequency-resolved terahertz spectroscopy, we unveil a high charge-carrier mobility up to 44 cm² V^-1 s^-1, among the highest reported for 2D COFs.