Preparation And Properties Of Graphene And Polyaniline Composite Sponge

Polyaniline (PANI) is a conductive polymer material with good thermalstability, high specific capacitance and easy synthesis, but pure PANI has theshortcoming of aggregation and poor electrochemical cycling stability. Graphene(GN) is the two-dimensional material of a single layer of carbon atoms in theform of a hexagonal close-packed lattice, and it has excellent properties such as,excellent mechanical properties, high surface area, high electrical conductivityand the like. The paper has combined GN with PANI to prepare the compositesponge of GN and PANI successfully. We have done a systematic study of theproperties of mechanical compression and electrochemistry.We prepare graphene oxide (GO) by two methods of Hummers andImproved Hummers respectively, and then we analyze and characterize thedegree of oxidation, the size of GO and yield by XRD and AFM. The resultsshow that Improved method has an advantage in the degree of oxidation, particlesize and yield, in particularly, it contains fewer impurities, large output, so weuse GO prepared by Improved method as the raw materials to the nextexperiment. We prepare a uniform dispersion of GO/PANI composites by in situpolymerization of aniline monomer in GO dispersions. Then we obtain theGO/PANI composite sponge by the process of freeze drying. And then we reducethe GO/PANI composite sponge in an atmosphere of hydrazine hydrate for1h toobtain the GN/PANI composite sponge.During the analysis of the mechanical compressional performance,experiments show that the elastic deformation of the10th compressive curve ofgraphene sponge or RGP1:0.6is almost100%atε=40%compared to the firstone, indicating that the sponge can restore elasticity completely. However, theelastic deformation of RGP1:3or RGP1:5is respectively98.3%and94.5%. Thestructure and composition of GO/PANI composite sponge is relatively uniform and GO has a better dispersion. The specific capacitance of GN/PANI compositesponge is higher than the GO/PANI composite sponge at the same proportion,such as the specific capacitance of RGP1:5is487F/g, however, GOP1:5is only152F/g, pure PANI397F/g, pure GN162F/g at the scan rate of2mV/s. And thespecific capacitance is going up with the increasing of the contents of PANI atdifferent proportions. PANI effectively improves the capacitive nature of theporous structure of GN. Though the specific capacitance of RGP1:5is487F/g, ithas a poor compressible performance. However, the specific capacitance ofRGP1:3is448F/g at the scan rate of2mV/s, and the plastic deformation issmaller than RGP1:5. Therefore, considering the compressibility andelectrochemical performance, RGP1:3has more comprehensive performance.