title: Carbon/MnO(2) double-walled nanotube arrays with fast ion and electron transmission for high-performance supercapacitors.
abstract: The novel carbon (C)/MnO2 double-walled nanotube arrays (DNTAs) are designed and fabricated via template-assisted electrodeposition. The unique DNTA architectures of C/MnO2 composites with high weight fraction of MnO2 allow high electrode utilization ratio and facilitate electron and ion transmission. In the half-cell test, the hybrid C/MnO2 DNTAs as electrodes show a large specific capacitance (Csp) of 793 F/g at the scan rate of 5 mV/s, high energy/power densities, and much enhanced long-term cycle stability. After 5,000 cycles, the Csp retention of C/MnO2 DNTAs keeps ∼97%, which is much larger than 69% of the MnO2 nanotube arrays (NTAs). The symmetrical supercapacitors (SSCs) composed of C/MnO2 DNTAs also show the predominant performance, such as large Csp of 161 F/g and high energy density of ∼35 Wh/kg, indicating that the C/MnO2 DNTAs is a potential electrode for supercapacitors. The high order pore passages, double-walled structures, hollow structures, and high conductivity are responsible for the superior performance of C/MnO2 DNTAs. Such hybrid C/MnO2 DNTAs may bring new opportunities for the development of supercapacitors with superior performance.
authors.affiliation: MOE Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University , Guangzhou, 510275 Guangdong, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.forename: Xue-Feng
authors.initials: XF
authors.lastname: Lu
authors.forename: Han
authors.initials: H
authors.lastname: Xu
authors.forename: Ye-Xiang
authors.initials: YX
authors.lastname: Tong
authors.forename: Gao-Ren
authors.initials: GR
authors.lastname: Li