Two-Dimensional Polymer Synthesized via Solid-State Polymerization for High-Performance Supercapacitors

• Published in: ACS nano Vol. 12; no. 1; pp. 852 - 860
• Main Authors: Liu, Wei, Ulaganathan, Mani, Abdelwahab, Ibrahim, Luo, Xin, Chen, Zhongxin, Rong Tan, Sherman Jun, Wang, Xiaowei, Liu, Yanpeng, Geng, Dechao, Bao, Yang, Chen, Jianyi, Loh, Kian Ping
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 23.01.2018
• Subjects: conjugated porous polymers; C−C coupling; solid-state polymerization; 2-D materials; supercapacitors
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.7b08354

Two-dimensional (2-D) polymer has properties that are attractive for energy storage applications because of its combination of heteroatoms, porosities and layered structure, which provides redox chemistry and ion diffusion routes through the 2-D planes and 1-D channels. Here, conjugated aromatic polymers (CAPs) were synthesized in quantitative yield via solid-state polymerization of phenazine-based precursor crystals. By choosing flat molecules (2-TBTBP and 3-TBQP) with different positions of bromine substituents on a phenazine-derived scaffold, C–C cross coupling was induced following thermal debromination. CAP-2 is polymerized from monomers that have been prepacked into layered structure (3-TBQP). It can be mechanically exfoliated into micrometer-sized ultrathin sheets that show sharp Raman peaks which reflect conformational ordering. CAP-2 has a dominant pore size of ∼0.8 nm; when applied as an asymmetric supercapacitor, it delivers a specific capacitance of 233 F g–1 at a current density of 1.0 A g–1, and shows outstanding cycle performance.