Pulse electrochemical incorporation of graphene oxide into polypyrrole films for supercapacitor electrode materials

•A Polypyrrole/Graphene oxide composite is electro-polymerized with pulse currents.•The effects of pulse current parameters on the capacitance are remarkable.•The composite exhibits a high specific capacitance and good stability.

In order to synthesize a PPy/GO composite for supercapacitor applications, a pulse electro-polymerization method was proposed to direct incorporate graphene oxide (GO) into polypyrrole (PPy) films without any additional dopants. The PPy/GO prepared by the pulse electro-polymerization (PC PPy/GO) exhibits a higher specific capacitance. A shorter pulse on time (ton) results in higher specific capacitance, but there is an optimum pulse current amplitude (IA) related to the highest specific capacitance. The PC PPy/GO film (IA = 4 mA cm−2, ton = 50 ms) has a high specific capacitance of 660 F g−1 estimated from galvanostatic charge-discharge in 1 M KCl at a current density of 0.5 mA cm−2. Stability tests for the PPy/GO yield long cycling life up to 1000 cycles with 10% decay in specific capacitance at charge-discharge current density of 10 mA cm−2 in the potential range of -0.5 to 0.5 VSCE.