Construction of crystalline and amorphous interface between FeS2 and polyaniline for enhanced electrocatalytic activity

Abstract We report a facile strategy to synthesize the FeS2/polyaniline/exfoliated graphene (FeS2/PANI /EG) with the formation of crystalline and amorphous interface for enhanced electrocatalytic activity. The PANI layer consists of nanowires roughly 100 nm in diameters and exhibits randomly distributed porous structure and the diameters of FeS2 distributed from 5 nm to 15 nm. The transmission electron microscopy image indicates the successful construction of crystalline and amorphous interface between FeS2 and PANI. In addition, the S element is doped into the PANI by forming C S covalent bond. Thus, the prepared FeS2/PANI/EG film shows excellent catalytic activity with the potential of 1.49 V at 10 mA cm−2 for oxygen evolution reaction in 1 M KOH solution, comparing with the 1.59 V and 1.65 V for FeS2/EG and PANI/EG, respectively.