Nitrogen-Doped Hierarchical Porous Carbon Derived from Bacterial Cellulose-Polyaniline Composite As High Performance Anode for Lithium-Ion Batteries

Abstract

An ever increasing demand for high energy and high power rating Lithium-ion batteries (LIB) for electric hybrid vehicles persuaded the development of novel electrode materials with large storage capability and faster kinetic process. Carbon nanomaterials, owing to their unique and tunable physical and chemical properties, have been widely investigated as anode materials for LIBs. Diversified strategies involving the synthesis of carbon materials with hierarchical structures (morphology and porosity), and heteroatom doping have shown significant improvement in electrochemical performance of these carbon nanomaterials. In consideration to this, we hereby demonstrate the synthesis and utilization of hierarchical nitrogen-doped porous carbon structures derived from bacterial cellulose-polyaniline nano-composites as a promising anode material for LIBs. Microstructural analysis of the derived carbon revealed the inheritance of fibrous backbone as obtained from bacterial cellulose along with nano-granular structure of polyaniline. The structural and electrochemical properties of as-derived porous carbon structures are analysed systematically by performing XRD, Raman spectroscopy, XPS, cyclic voltammetry, galvanostatic charge/discharge studies and impedance spectroscopy. These results unveiled significantly large reversible capacities of 432, 233, and 127 mAh/g at 1, 5, and 10 C-rate respectively with excellent capacity retention. The energy and power densities of these hierarchical porous carbon structures were increased by 54% and 41% respectively when compared to pure bacterial cellulose derived carbon. This enhanced electrochemical performance may be attributed to the combined effect of interconnected micro-meso porous network of hard carbon along with nitrogen doping. The core-shell structure of this derived carbon accommodates the volume changes during lithium-ion insertion and de-insertion, rendering excellent cyclic stability even at high C rates without causing pulverization.