Development of 2-Amino-4-phenythiazole Based Carbon Materials /Composites as Anode for Lithium and Sodium Ion Batteries

Abstract

Nitrogen and sulphur codoped carbon materials (NSCMs-x) and ZnS/Carbon composites (ZnS/NSC-x) have been successfully synthesized, characterized and investigated as anode for lithium and sodium battery application. The synthesized NSCM-x and ZnS/NSC-x were characterized by Raman spectroscopic analysis (RS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), surface area analysis (BET), particle size distribution analysis (PSD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The physiochemical analysis of NSCMs-x and ZnS/NSC-x showed graphitization and also successful doping of nitrogen and sulphur. Nitrogen is present in three different types of configurations (pyridinic N-6, pyrrolic N-5, and quaternary N-Q). However, sulphur is present in covalent bonding with carbon and in oxidative form as sulfoxides. The moderate surface area with porous and graphitic sheets like morphology was achieved in these materials. The electrochemical investigations were performed through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The synthesized heteroatom co-doped composites (ZnS/NSC-x), used as the positive electrode in a lithium-ion battery, gives better performance than pure ZnS both in terms of rate capability and capacity retention. Ammonium sulphate was also investigated for its dual role as heteroatom dopant and as an activating agent for the preparation of NSCMs-x. The synthesized NSCM-x were tested as positive electrode in sodium batteries and they give good storage capacities. Kinetic analysis through multi-scan voltammetry was also performed to investigate the storage phenomenon. Moreover, the comparison of the materials prepared at different temperatures showed the best performance at 800°C which is ascribed to the better compromise of graphitization degree and dopants quantity at the said temperature. In addition the effect of mass loading and calendering on the electrochemical performance of electrodes was also investigated. The storage capacities of uncalendered electrodes were found relatively higher than the calendered ones. However, the improved cyclic stability was observed in case of calendered electrodes. On studying the effect of mass loading the poor adhesion was observed for the heavy mass loaded electrodes and the mass loading of up to 4 mgcm-2 was found to be stable for ZnS/NSC-800.