Electrolytic Conversion of Natural Graphite into Carbon Nanostructures with Enhanced Electrical Conductivity and Na-ion Storage Performance

Abstract

This article reports on the electrochemical exfoliation of natural graphite into electrolytic carbon nanostructure (ECN) containing three dimensional clusters of onion-like carbon nanoparticles and carbon nanotubes. The exfoliation process is conducted in molten LiCl-NaCl at 740 °C. The morphological and structural characteristics of ECN are correlated to its electrical and electrochemical performances. Due to the presence of highly graphitized nanotubes, the bulk electrical conductivity of ECN is found to be remarkable at 9.7 S cm−1. Also, an enlarged d002 interlayer spacing is recorded on onion-like carbon nanoparticles present in ECN, enhancing the Na-ion storage performance of the material, with the reversible capacity of 175 mAh g−1 recorded after 385 Na-ion insertion and extraction cycles at the current density of 200 mA g−1. This article discusses the molten salt conversion of natural graphite minerals into nanostructured carbon with enhanced electrical conductivity and Na-ion storage performance.