Porous N-doped carbon/MnO2 nanoneedles for high performance ionic liquid-based supercapacitors

• Published in: Materials letters Vol. 296; p. 129837
• Main Authors: Zhu, Hangtian, An, Yafei, Shi, Minjie, Li, Ziqi, Chen, Nianting, Yang, Cheng, Xiao, Peng
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.08.2021; Elsevier BV
• Subjects: Carbon; Carbon nanosheets; Carbon nitride; Electrical resistivity; Electrodes; Electrolytes; Energy storage; Flexible supercapacitor; Flux density; Ionic liquid; Ionic liquids; Ions; Manganese dioxide; Manganese oxide; Materials science; Supercapacitors; Carbon nanosheets; Flexible supercapacitor; Manganese oxide; Ionic liquid; Energy storage
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2021.129837

[Display omitted] •Two-dimensional porous N-doped carbon (2D-PNC) is derived from graphitic carbon nitride.•MnO2 nanoneedles are wrapped by 2D-PNC nanosheets to obtain composite electrode.•Abundant active sites and high conductivity of composite electrode are presented.•Such composite electrode shows favorable electrochemical behaviors in IL electrolyte.•A high-performance packaging flexible SC using IL electrolyte has been assembled. Fabricating supercapacitors (SCs) based on ionic liquid (IL) as an electrolyte is an effective strategy to enhance the devices' operating voltage and energy density. Herein, a novel MnO2-based electrode with superior electrochemical behaviors in IL electrolyte has been put forward. Remarkably, MnO2 nanoneedles are steadily wrapped by two-dimensional porous N-doped carbon (PNC) which is derived from graphitic carbon nitride (g-CN) as the sacrificial template. Beneficial from abundant active sites, suitable porous structure and enhanced electric conductivity, the resultant MnO2/PNC electrode exhibits large specific capacitance, remarkable rate capability, and favorable electrochemical kinetics in IL electrolyte. As a result, a high-performance flexible SC with long-term cycling stability has been assembled based on the MnO2/PNC electrode and IL electrolyte, indicating its potential applications in flexible and portable electronics.