The Application Of Polypyrrole-based Nanocarbons In Electrochemical Energy Storge

In the development of electric double-layer capacitance (EDLC) supercapacitor, aproper control over the specific surface area and the pore size are crucial to ensure a goodperformance of the supercapacitor. However, the limited energy storage capacity of EDLCrestrict their applications due to unavoidable aggregation and small effective surface area.A simple way in developing high-capacitance supercapacitors is combining the EDLC andpseudocapacitance. In addition, three-dimensional (3D) carbon nanostructures made bycombining two-dimensional (2D) material and one-dimensional (1D) material togetherhave attracted great interest in recent researches, can be achieved with excellent workfunctions as electrode. Therefore, we focus on the1D/2D composites with goodelectrochemical capacitance behavior. The details are as follows：(1) By the reactive self-degraded template-directed synthesis and further carbonization,N-and O-doped carbonaceous nanotubes from conducting polymer (polypyrrole) precursorhave been prepared. After being chemically activated by KOH, specially, with the weightratio of KOH to polypyrrole nanotubes of2and4, two samples of activated carbonaceouspolypyrrole nanotubes (ACPN-2and ACPN-4) with an uncapped morphology wereobtained. The ACPN-4possesses high heteroatom content (14.85%) and specific surfacearea (1226m2g-1), and exhibits a reversible capacitance of470F g-1at the current densityof0.2A g-1, and280F g-1even at a higher current density of10A g-1. Moreover, thesenanotubular structured materials have also shown excellent cycling performance with nocapacitance loss over10000cycles. Furthermore, these carbonaceous nanotubes achieved ahigh CO2adsorption uptake of3.9mmol g-1at273K and2.5mmol g-1at298K. (2) A facile one-pot method was introduced to construct three-dimensional (3D)nanohybrid composites by combining one-dimensional (1D) carbonaceous polypyrrolenanotubes with two-dimensional (2D) graphene sheets. The complex of methyl orange(MO) and FeCl3was used as a reactive self-degradable seed template promoting theassembly of polypyrrole (PPy) into hollow nanotubular structures on graphene oxide (GO)substrate, and was followed by reduction and carbonization. Importantly, the morphologiesof3D nanostructure can be controlled by adjusting the ratios of pyrrole to GO. Theresulting material used as superacpacitor show high specific capacitance, good ratecapability and still retain94.5%of the initial capacitance even after10000cycles.