Effective improvement in capacitance performance of polypyrrole assisted by black phosphorus

The composite of polypyrrole and black phosphorus (PPy/BP) has been successfully prepared by the in situ chemical method through the polymerization of pyrrole (Py) on the surface of BP flake. Characterization results show that it present well-dispersed morphological and P–C bonding in PPy/BP. It is evident that the adding of BP exactly brings the changes in morphological and structure. To verify the existence of BP and to obtain the structure relationship between BP and PPy, an auxiliary experiment has been designed and the corresponding XRD and TEM results clearly display that BP is wrapped by PPy. All these morphology and structural characteristics are conductive to the excellent electrochemical performance of PPy/BP. The electrochemical results show that, the capacity of PPy/BP is 515 F/g at 1 A/g, which is ~ 1.7 times (70%) higher than that of PPy and ~ 7.1 times than that of BP. The capacity of PPy/BP reaches stable value within 200 circles, which is faster than that of PPy within 450 circles. The stable value of PPy/BP is still ~ 1.5 times (48%) higher than that of PPy within 1000 circles, presenting better cycling performance.