High-Stacking-Density, Superior-Roughness LDH Bridged with Vertically Aligned Graphene for High-Performance Asymmetric Supercapacitors.
Small
; 13(37)2017 10.
Article
em En
| MEDLINE
| ID: mdl-28786542
ABSTRACT
The high-performance electrode materials with tuned surface and interface structure and functionalities are highly demanded for advanced supercapacitors. A novel strategy is presented to conFigure high-stacking-density, superior-roughness nickel manganese layered double hydroxide (LDH) bridged by vertically aligned graphene (VG) with nickel foam (NF) as the conductive collector, yielding the LDH-NF@VG hybrids for asymmetric supercapacitors. The VG nanosheets provide numerous electron transfer channels for quick redox reactions, and well-developed open structure for fast mass transport. Moreover, the high-stacking-density LDH grown and assembled on VG nanosheets result in a superior hydrophilicity derived from the tuned nano/microstructures, especially microroughness. Such a high stacking density with abundant active sites and superior wettability can be easily accessed by aqueous electrolytes. Benefitting from the above features, the LDH-NF@VG can deliver a high capacitance of 2920 F g-1 at a current density of 2 A g-1 , and the asymmetric supercapacitor with the LDH-NF@VG as positive electrode and activated carbon as negative electrode can deliver a high energy density of 56.8 Wh kg-1 at a power density of 260 W kg-1 , with a high specific capacitance retention rate of 87% even after 10 000 cycles.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Small
Assunto da revista:
ENGENHARIA BIOMEDICA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
China