Three-dimensional Nitrogen-doped graphene as binder-free electrode materials for supercapacitors with high volumetric capacitance and the synergistic effect between nitrogen configuration and supercapacitive performance. (10th November 2016)

• Record Type: Journal Article
• Authors: Zhao, Xiao; Dong, Hanwu; Xiao, Yong; Hu, Hang; Cai, Yijin; Liang, Yeru; Sun, Luyi; Liu, Yingliang; Zheng, Mingtao
• Is Part Of: Electrochimica acta. Volume 218(2016)
• Page Start: 32
• Page End: 40
• Publication Date: 2016-11-10
• Subjects: nitrogen doped graphene -- three dimensional structure -- supercapacitors -- volumetric capacitance -- nitrogen configuration; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.09.096
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Three dimensional nitrogen graphene (3DNG) was synthesized by hydrothermal method. The 3DNG binder-free electrode exhibits excellent electrochemical performance. Nitrogen-doping can improve the conductivity and wettability of graphene. N-configurations play an important role in enhancing the electrochemical behavior. Abstract: Three dimensional nitrogen-doped graphene (3DNG) with high nitrogen content and improved electrochemical performance is successfully prepared by a facile, lost-cost hydrothermal method with ammonia as reducing-doping agent. The as-prepared 3DNG exhibits a hierarchical and interconnected porous network, which offers favorable pathways for electrolyte penetration and transportation. Remarkably, as binder-free electrode in aqueous electrolyte, the resultant 3DNG-2 with both high nitrogen content (7.71 at%) and large active material density (1.31 g cm −3 ) exhibits an ultrahigh volumetric capacitance of 437.5 F cm −3 (334.0 F g −1 ) at current density of 0.5 A g −1 and superior cycling stability (93% capacitance retention after 20 000 cycles at high current density of 10 A g −1 ). Further analyses indicate that the N-configurations are of great significance to the improvement of electrochemical behavior as well as the N-content. This work provides an effective way to synthesize 3DNG with excellent electrochemical properties for high performance supercapacitor and promotes the in-depth understanding of the enhancement mechanism of N-doping to supercapacitor performance.