Free-standing microporous paper-like graphene films with electrodeposited PPy coatings as electrodes for supercapacitors

Free-standing microporous paper-like graphene films with electrodeposited polypyrrole (PPy) coatings were prepared. The microporous structures were produced by employing PS microspheres as sacrificial templates. PPy was coated on the films using an electrochemical deposition process to further improve the performance of these graphene electrode materials. The electrochemical performance of PPy coated microporous graphene films is evaluated and compared with solid graphene films. The results reveal that the incorporation of PPy and microporous structures significantly improve the electrochemical performance of graphene based electrodes for supercapacitors. Microporous films have higher capacitance than their solid counterparts although they have slightly lower conductivity, which reveals that microporous structures play an important role in the electrochemical performance of the electrode materials. The PPy coated microporous graphene films have the better electrochemical performance than uncoated counterparts, which indicates that PPy coatings have significant effects on graphene based electrodes. This in-depth research on free-standing microporous paper-like graphene with electrodeposited PPy coatings provides a new route to combine the advantages of both graphene and PPy so as to produce high performance electrodes for supercapacitors.