Three-dimensional nitrogen-doped dual carbon network anode enabling high-performance sodium-ion hybrid capacitors

It is urgent for sodium-ion hybrid capacitors (SIHCs) to exploit a porous carbon anode that integrates high reversible specific capacity, rapid kinetics and superb cyclability. Herein, a three-dimensional dumpling like glyururil-derived porous carbon@RGO composite (GLCG) constructed from nitrogen-doped (10.29 at.%) hierarchical porous carbon filling and highly conductive flexible RGO wrapper is synthesized. As for the Na half-cell, GLCG anode delivers high reversible specific capacity (282 mAhg(-1) at 0.05 Ag-1) as well as superb rate capability (122.8 mAhg(-1) at 10 Ag-1) and lifespan (30 0 0 cycles at 2 Ag-1). Moreover, the origin of the excellent sodium-ion storage properties of GLCG is revealed by in-depth mechanism analysis. Consequently, a SIHCs with GLCG anode is constructed, which displays high energy density of 108 Wh kg(-1), high power density of 14.2 kW kg(-1) and long lifespan of 66% capacity retention after 5000 cycles at 2 Ag-1. This work provides an alternative avenue for the exploitation of high-performance carbon-based SIHCs anode. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

A three-dimensional dumpling-like glyururil-derived porous carbon@RGO composite with high reversible specific capacity, superb rate capability, and long lifespan is synthesized. The excellent sodium-ion storage properties of the composite are revealed through in-depth mechanism analysis.