Fabrication of Mn3O4-carbon nanotube composites with high areal capacitance using cationic and anionic dispersants.
J Colloid Interface Sci
; 512: 758-766, 2018 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-29112926
ABSTRACT
Mn3O4-multiwalled carbon nanotube (MWCNT) electrodes for supercapacitors with high active mass loadings have been fabricated with the goal of achieving a high area normalized capacitance (CS) and enhanced capacitance retention at high charge-discharge rates. Poly(4-styrenesulfonic acid-co-maleic acid) sodium salt P(SSA-MA) was used as a charging and dispersing agent for the fabrication of Mn3O4. The unique bonding properties of the MA monomers allowed efficient P(SSA-MA) adsorption on Mn3O4, whereas SSA monomers imparted a negative charge. Cationic ethyl violet (EV) and pyronin Y (PY) dyes were used for dispersion and charging of MWCNT. Good dispersion of the individual components and their electrostatic heterocoagulation facilitated efficient mixing, which allowed enhanced capacitive behavior at mass loadings of 28.4â¯mgâ¯cm-2, which meet requirements for practical applications. The highest capacitance of 2.8â¯Fâ¯cm-2 was obtained at a scan rate of 2â¯mVâ¯s-1 for the composites, prepared using PY. However, the composites, prepared using EV showed better capacitance retention of 88% in the scan rate range of 2-100â¯mVâ¯s-1 and the capacitance of 2.1â¯Fâ¯cm-2 was obtained at a scan rate of 100â¯mVâ¯s-1. The composites showed activation behavior during cycling, which resulted in a capacitance increase and electrical resistance reduction. The results of this investigation showed that Mn3O4-MWCNT composites, prepared by new colloidal methods are promising materials for practical applications in electrochemical supercapacitors.
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01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Colloid Interface Sci
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Canadá