Understanding the dual function of oxygen-containing groups in fabricating PANi electrodes and Zn-PANi battery

Abstract

The study of conductive polymer during the past decades had proved that protonic acidic medium could promoted it with superior electrochemical activity, but the acidic medium will result to the corrosion of zinc anode in Zn-PANi battery. In this work, an electrochemically oxidized graphite substrate was applied as substrate (GE) for the fabrication of polyaniline (PANi) electrode, the functional groups were proved with dual function. Firstly, it benefit the growth of PANi, the experiments and DFT calculation indicated that the oxidized graphene surface owns a more hydrophilic surface with higher adsorption energy, the deposition efficiency was 12 times higher than on pristine graphite (GA). Secondly, as the oxygen-containing groups can functioned as local proton reservoir, the produced GE-based Zn-PANi battery shown higher electrochemical activity and reversibility. The capacity of GEP600-based Zn-PANi battery was 0.057 mAh cm−2 at current density of 0.5 mA cm−2 even after 1000 cycles.