Premium
Three‐Dimensional Hierarchically Mesoporous ZnCo 2 O 4 Nanowires Grown on Graphene/Sponge Foam for High‐Performance, Flexible, All‐Solid‐State Supercapacitors
Author(s) -
Moon In Kyu,
Yoon Seonno,
Oh Jungwoo
Publication year - 2017
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201602447
Subject(s) - supercapacitor , materials science , capacitance , graphene , electrode , mesoporous material , electrochemistry , electrolyte , chemical engineering , oxide , nanotechnology , horizontal scan rate , metallurgy , catalysis , chemistry , organic chemistry , cyclic voltammetry , engineering
To achieve high energy storage on three‐dimensional (3D) structures at low cost, materials with high power and long cycle life characteristics have to be developed. We synthesized ZnCo 2 O 4 /reduced graphene oxide (rGO) binary composites in commercial sponges. ZnCo 2 O 4 nanosheets were grown on the surface of GO/sponge through a hydrothermal reaction. The resulting flexible, free‐standing ZnCo 2 O 4 /rGO/sponge electrodes were used as the electrodes in a symmetric supercapacitor. ZnCo 2 O 4 /rGO/sponge electrodes have a large specific capacitance of 1116.6 F g −1 at a scan rate of 2 mV s −1 in aqueous electrolyte. The all‐solid‐state flexible supercapacitor is assembled based on ZnCo 2 O 4 /rGO/sponge electrodes, which show excellent electrochemical performances with a specific capacitance of 143 F g −1 at a current density of 1 A g −1 . The as‐fabricated supercapacitor also exhibits excellent cycling stability (93.4 % capacitance retention after 5000 cycles) and exceptional mechanical flexibility. These results demonstrate the potential of ZnCo 2 O 4 /rGO/sponge as an electrode in flexible, high‐performance supercapacitors.