Green Synthesis and Thermal Encapsulation of Organic Cathode for Aqueous Zn Battery

Abstract

Aqueous zinc batteries are increasingly gaining attention of the researchers in recent years because of their environmental and user friendliness as well as the economic benefits of the zinc metal. Herein we report a ferrocene based organic cathode synthesized by following green chemistry principle and stabilized by low temperature thermal encapsulation in multiwalled carbon nano tubes (MWCNTs) for stable electrochemical performance. Successful intercalation was confirmed by XRD, Raman, FTIR spectra, TEM-HAADF imaging. Without encapsulation, material exhibited initial capacity of 64.7 mAhg−1 which was drastically faded with time due to dissolution of active material. However, by low temperature thermal encapsulation, the capacity was remarkably improved to 71.3 mAhg−1 with 94% columbic efficiency and 91% capacity retention at a current density of 75 mAg−1 in a 100 charge/discharge cycles. The stability of the electrode has been explained on the basis of a friendly host-guest interaction between CNTs and the organic molecules by π-π stacking, dipole-dipole and dipole induced dipole interactions with detailed electrochemical and spectroscopic characterization. From this study we conclude that the thermal intercalation in MWCNTs has been found to be excellent method to stabilize the electrode materials in battery application.