Self-arranged polythiophene on multi-walled carbon nanotube templated composites: Synthesis and application in rechargeable aluminium battery

Abstract

This work demonstrates the application of polythiophene/multi-walled carbon nanotube (PTh/MWCNT) composite as electrode material for rechargeable aluminium battery (RAB) consisting Al plate as negative electrode. Chemical in-situ oxidative synthetic procedure was followed for obtaining PTh/MWCNT composite, which defines one-dimensional morphology of as synthesized mixture, deciphered through FESEM and HRTEM analysis. The polymer's successful nanocomposite formation was confirmed through FTIR analysis and EDS elemental mapping. Further application of PTh/MWCNT as cathode against Al anode in 1.5:1 molar ratio of AlCl3:[EMIm]Cl signify the positive electrochemical behaviour. Cyclic voltammetry of the cells show well-defined redox-peaks, demonstrating the possible chloroaluminate ions doping/de-doping at the active electrode. Galvanostatic charge-discharge analysis of the cell yields high specific capacity of ~216mAh/g, retaining ~100% coulombic efficiency. The cells have shown excellent reversible cycling over different C-rates. XPS analysis of the cycled PTh/MWCNT electrode shows the existence of multi-polaron state associated with S from thiophene of polymer unit affirming the de/-doping chloroaluminate ions occurred. The positive prospect of PTh in its pristine or composite form defines a promising electrode material that deserves intensive study and further development.