Journal
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
Volume 465, Issue -, Pages 32-38Publisher
ELSEVIER
DOI: 10.1016/j.colsurfa.2014.10.043
Keywords
Porous graphene; MnO2 particles; Supercapacitor; Freeze-drying
Categories
Funding
- National Nature Science Foundation of China [51202130]
- Shandong Provincial Natural Science Foundation, China [ZR20128Q001]
- Scientific Research Foundation for the Returned Overseas Chinese Scholars
- State Education Ministry and State Key Laboratory of Electroanalytical Chemistry Open Foundation [SKLEAC201304]
Ask authors/readers for more resources
Three dimensional (3D) porous graphene-MnO2 (PGR-MnO2) composites as electrode materials for supercapacitors were fabricated via deposition of MnO2 particles on 3D PGR produced from freeze-drying method. Field emission scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy were used to characterize morphologies and composition of the produced PGR-MnO2 composites. By immersing PGR into 0.1 M KMnO4/K2SO4 for different time, it was found that MnO2 particles with the size of about 200 nm were formed and uniformly distributed on the GR sheets. The obtained PGR-MnO2 composites still remained 3D interpenetrating porous structures. Electrochemical methods including cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge were carried out to investigate electrochemical properties and capacitive performance. The results showed that the PGR-MnO2-2 h composite (immersing the PGR into 0.1 M KMnO4/K2SO4 for 2 h) gave the best capacitive performance among these produced composites. The PGR-MnO2-2 h composite gave the maximum specific capacitance of 800 F g(-1) with the maximum energy density of 40 W h kg(-1) at the current density of 0.1 A g(-1). The good capacitive performance was attributed to the unique 3D porous structure of the PGR-MnO2 composites and the synergistic effect of GR with high conductivity and MnO2 particles with good pseudocapacitive properties. (C) 2014 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available