Water-in-salt electrolyte ion-matched N/O codoped porous carbons for high-performance supercapacitors

• Published in: Chinese chemical letters Vol. 31; no. 2; pp. 579 - 582
• Main Authors: Yan, Jingjing, Zhu, Dazhang, Lv, Yaokang, Xiong, Wei, Liu, Mingxian, Gan, Lihua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2020; College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China; Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China%College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China%Key Laboratory for Green Chemical Process of Ministry of Education, School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430073, China%Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China
• Subjects: High energy density; N/O Codoped Porous carbon; Pore/ion size matching; Symmetrical supercapacitor; Water-in-salt electrolyte; Symmetrical supercapacitor; Water-in-salt electrolyte; Pore/ion size matching; High energy density; N/O Codoped Porous carbon
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2019.05.035

N O−1 codoped porous carbons synthesized via a Schiff-base reaction show dominant micropores matched with the ionic sizes of 2.2 V LiTFSI water-in-salt electrolyte, yielding a high energy density of 30.5 Wh kg−1 and high stability for supercapacitors.
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Pore size and distribution in carbon-based materials are regarded to be a key factor to affect the electrochemical capacitive performances of the resultant electrodes. In this study, nitrogen and oxygen codoped porous carbons (NOPCs) are fabricated based on a simple Schiff-base reaction between m-phenylenediamine and terephthalaldehyde. The NOPCs have tunable morphologies, high surface areas, abundant heteroatom doping. More importantly, the carbons show a dominant micropores of 0.5–0.8 nm, comparable to the ionic sizes of LiTFSI (Li+ 0.069 nm; TFSI– 0.79 nm) water-in-salt electrolyte with a high potential window of 2.2 V. Consequently, the fabricated symmetric supercapacitor gives a high energy output of 30.5 Wh/kg at 1 kW/kg, and high stability after successive 10,000 cycles with ∼96.8% retention. This study provides promising potential to develop high-energy supercapacitors.