||MnO2/CNF nanofiber composite material used for batteries and capacitors is produced by stabilization, dipping and carbonization on electrospun polyacrylonitrile(PAN) nanofiber paper in this experiment. This research uses dip-coating to dope manganese oxide into carbon nanofiber in order to enhance electro capacity. Scanning electron microscope (SEM), Transmission electron microscope (TEM), thermal gravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and cyclic voltammetry (CV) are utilized to analyze and research in this experiment.|
Under SEM, electrospun PAN nanofiber bended, melted, aggregated and swelled after dipping in manganese sulfate solution, which revels the breakdown of fiber structure. CNF after being dopped for 1 hour contains only 0.65 % of Mn element from EDS analysis. Small number of MnO2 particle can be seen in dipped CNF via TEM. Dipped CNF has higher retention (67 %) yield than undipped CNF (34 %), revealed by TGA result. XRD shows peak shifts without new peak appeared, attributed to breakdown of d-spacing in the structure by acid. CV curves show narrow shape and the undipped CNF has highest specific capacity and the specific capacity lowers severely from 7.04 F/g to 1.18 F/g after 5 minutes dipping process. With dipping by 60 minutes, specific capacity of CNF raises slightly to 2.23 F/g. CNF that dipped after carbonization has capacity of 14.67 F/g.