Open AccessHierarchical VOOH hollow spheres for symmetrical and asymmetrical supercapacitor devices
Author(s) -
Xuyang Jing,
Cong Wang,
Wenjing Feng,
Na Xing,
Hanmei Jiang,
Xiangyu Lu,
Yifu Zhang,
Changgong Meng
Publication year - 2018
Publication title -
royal society open science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 51
ISSN - 2054-5703
DOI - 10.1098/rsos.171768
Subject(s) - supercapacitor , materials science , capacitance , dielectric spectroscopy , cyclic voltammetry , spheres , electrode , crystallinity , electrochemistry , nanotechnology , nanoparticle , chemical engineering , optoelectronics , composite material , chemistry , physics , astronomy , engineering
Hierarchical VOOH hollow spheres with low crystallinity composed of nanoparticles were prepared by a facile and template-free method, which involved a precipitation of precursor microspheres in aqueous solution at room temperature and subsequent hydrothermal reaction. Quasi-solid-state symmetric and asymmetric supercapacitor (SSC and ASC) devices were fabricated using hierarchical VOOH hollow spheres as the electrodes, and the electrochemical properties of the VOOH//VOOH SSC device and the VOOH//AC ASC device were studied by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS). Results demonstrated that the electrochemical performance of the VOOH//AC ASC device was better than that of the VOOH//VOOH SSC device. After 3000 cycles, the specific capacitance of the VOOH//AC ASC device retains 83% of the initial capacitance, while the VOOH//VOOH SSC device retains only 7.7%. Findings in this work proved that hierarchical VOOH hollow spheres could be a promising candidate as an ideal electrode material for supercapacitor devices.