N,O-codoped porous carbon nanosheets for capacitors with ultra-high capacitance

Abstract

Significant enhancement of energy density of electrical double layered capacitors is a major challenge for electrochemical capacitors to conquer the emerging field of large scale renewable energy storage. The enhancement of specific capacitance is an effective strategy to obtain higher energy density. Addition of redox mediator in the electrolyte as pseudocapacitive sources could enhance the specific capacitance, but well-coupled electrode materials should be developed as well. Herein, as a proof-of-concept experiment, N, O-codoped porous carbon nanosheets have been fabricated, wherein graphene oxide is employed as both oxygen source as well as structure directing agent. Unexpectedly, the obtained electrode materials endow electrical double layered capacitors with excellent capacitive performances, including the ultra-high specific capacitance (5073.5 F g −1 ) and excellent cycling stability, which could be attributed to the synergy of morphology and surface chemistry of N, O-codoped porous carbon nanosheets. These results would form the basis for an unprecedented perspective in the development of next generation electrode materials for electrical double layered capacitors.

Recent advances in flexible supercapacitors based on carbon nanotubes and graphene

“…In comparison with batteries, both types of supercapacitors generally offer higher power densities, but lower energy densities. With the rapid development of flexible electronics, various elec-trode materials including carbon materials [7,[19][20][21], metal oxides/hydroxides [22][23][24], conductive polymers [25][26][27] and their associated composites have been developed to fabricate flexible supercapacitors.…”

N‐doping Hierarchical Porosity Carbon from Biowaste for High‐Rate Supercapacitive Application

“…The element mapping clearly reveals that the nitrogen element is dispersed homogeneously in the SAC‐4 sample. Oxygen–containing groups can provide pseudo‐capacitance, which also contribute to the enhancement of overall capacitive performance …”

“…The content of N‐5 and N−X can contribute to the faradaic reaction‐based pseudocapacitance effect, which can enhance the specific capacitance of the sample . It is reported that N−Q exhibit electron donor ability and can facilitate electron transfer to improve the electrical conductivity ,. The electrical conductivity of SAC‐4 is estimated to be 848 S m −1 , which is higher than SAC‐2 (618 S m −1 ), SAC‐6 (485 S m −1 ).…”

Research Progress in MnO2–Carbon Based Supercapacitor Electrode Materials

“…In addition, the capacitance retention rate of up to 95.2%. As a result, flexible fibrous supercapacitors have shown great potential in portable and wearable electronic devices, creating new opportunities for sustainable development and self‐development in nanometer equipment in the near future …”