Synthesis Of Porous Carbon And Composite Material And Its Supercapacitor Performance

The thesis aim is to synthesis the porous carbon and composite materials with theapplication for supercapacitors. We synthesis the porous carbon nanofibers throughelectrospinning method and composite materials by hydrothermal method.The main research contents of this thesis are as follows:(1) The porous carbon fibers have been synthesized by an electrospinning method with PF resin and PVP as carbon sources and triblock copolymer Pluronic(P123) and tetraethyl orthosilicate(TEOS) as mesoporous templates. Pluronic(P123), tetraethyl orthosilicate(TEOS) and PVP show the significant role in sustain the fiber structure. The results suggest that the obtained porous carbon fibers material possesses a high surface area of 2095 m2 g-1. The electrode achieves a high specific capacitance of 252F g-1 at a scan rate of 0.5 A g-1. The porous carbon fibers displays an excellent specificcapacitance. Furthermore, cyclic test indicate the best high cycle stability.(2) The complex of porous carbon fibers material and Mn O2 was prepared using asimple hydrothermal method(PCNFs@Mn O2). The PCNFs@Mn O2 electrode possesses a high specific capacitance of 520 F g-1 at 0.5 A g-1. Furthermore, cyclic testindicate the best high cycle stability(90%). The superior electrochemical performanceof PCNFs@Mn O2 is mainly attributed to its hierarchical porous structure. ThePCNFs@Mn O2 displays the better specific capacitance and the better high cycle stability.(3) Ni(OH)2 nanosheet coating the porous carbon fibers@Mn O2(CF@Mn O2@ Ni(OH)2) prepared by an easy hydrothermal method is reported, meanwhile, with this electrode material and 6 M KOH solution electrolyte, a new type of high-energy-density symmetrical supercapacitor has been designed. As a result, the CF@Mn O2@Ni(OH)2 hybrid electrode exhibits extremely best specific capacitance(2005 F g-1 at 0.5 A g-1), a high energy density of 44.9 Wh kg-1. These results suggest that CF@Mn O2@Ni(OH)2 possess specific capacitance.