ZnO@MnO2 Core-Shell Nanofiber Cathodes for High Performance Asymmetric Supercapacitors
2019/11/27 21:27:05
admin
Asymmetric supercapacitors (ASCs) with aqueous electrolyte medium have recently become the focus of increasing research. For high performance ASCs, selection of cathode materials play a crucial role, and core-shell nanostructures are found to be a good choice. We successfully synthesized, ZnO@MnO2 core-shell nanofibers (NF's) by modification of high-aspect-ratio-electtospun ZnO NFs hydro thermally with MnO2 nanoflakes. High conductivity of the ZnO NFs and the exceptionally high pseudocapacitive nature of MnO2 nanoflakes coating delivered a specific capacitance of 907 Fg(-1) at 0.6 Ag-1 for the core-shell NFs. A simple and cost-effective ASC construction was demonstrated with ZnO@MnO2 NFs as a battery-type cathode material and a commercial quality activated carbon as a capacitor-type anode material. The fabricated device functioned very well in a voltage window of 0-2.0 V, and a red-LED was illuminated using a single-celled fabricated ASC device. It was found to deliver a maximum energy density of 17 Whkg(-1) and a power density of 6.5 kWkg(-1) with capacitance retention of 94% and Coulombic efficiency of 100%. The novel architecture of the ZnO@MnO2 core-shell nanofibrous material implies the importance of using simple design of fiber-based electrode material by mere changes of core and shell counterparts.

0
网友评论
请遵循相关法律法规,理性发言
查看更多回复