Amorphous carbon nanosheets suitable for deep eutectic solvent electrolyte toward cryogenic energy storage

Yi Zhang; Guoli Zhang; Juncheng Wu; Jiangyong Yu; Gang Li; Taotao Guan; Kaiying Wang

doi:10.1016/j.jcis.2023.07.156

Amorphous carbon nanosheets suitable for deep eutectic solvent electrolyte toward cryogenic energy storage

J Colloid Interface Sci. 2023 Nov 15;650(Pt B):2003-2013. doi: 10.1016/j.jcis.2023.07.156. Epub 2023 Jul 26.

Authors

Yi Zhang¹, Guoli Zhang², Juncheng Wu¹, Jiangyong Yu¹, Gang Li³, Taotao Guan⁴, Kaiying Wang⁵

Affiliations

¹ Institute Energy Innovation, College of Materials Science and Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, PR China; CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, PR China.
² Institute Energy Innovation, College of Materials Science and Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, PR China; CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, PR China. Electronic address: zguoli@outlook.com.
³ Institute Energy Innovation, College of Materials Science and Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, PR China.
⁴ Institute Energy Innovation, College of Materials Science and Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, PR China; CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, PR China. Electronic address: guantt@hotmail.com.
⁵ Institute Energy Innovation, College of Materials Science and Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, PR China; Department of Microsystems, University of South-Eastern Norway, Horten 3184, Norway. Electronic address: Kaiying.Wang@usn.no.

PMID: 37531667
DOI: 10.1016/j.jcis.2023.07.156

Abstract

The emerging deep eutectic solvent (DES) electrolyte has great potential in realizing commercial-scale application of electric double-layer capacitors (EDLCs) served in low temperature environment. That goal, however, rests with how to design the interface structure of electrode materials for well-matching with DES electrolyte. Herein, porous carbon nanosheets (PCNs) were obtained from coal tar pitch through Friedel-Crafts acylation reaction and melting salt intercalation process. The morphology, specific surface area and porosity of porous carbon nanosheets were regulated by tailoring the abundance of the dangling-bonds grafted on the CTP molecules. Profiting from the large specific surface area, suitable pore structure and good two-dimensional structure to provide more active sites and enhance ion transport capacity, the PCNs-0.10 delivers a maximal specific capacitance of 504F g^-1 at 0.1 A g^-1, which is overmatch than most of previously reported for other carbon materials. As-assembled symmetrical EDLCs using K⁺ DES electrolyte, can be assembled to work at -40 °C to 75 °C and exhibit satisfactory energy density. The strategy proposed here has opened a new way for exploring the large-scale preparation of electrode materials suitable for ultra-low temperature capacitors.

Keywords: Coal tar pitch; Non-planar macromolecules; Porous carbon nanosheets; Ultra-low temperature capacitor.