Carbon material derived from biomass: A study of structural and electrochemical performances for dual-carbon sodium-ion batteries

Abstract Biomass is one of the attractive, renewable, widely available, and cost-effective precursors to obtain carbon. In this work, the carbon-based material derived from coconut shell was produced by carbonization method that is applicable for anode materials especially dual-carbon sodium-ion batteries. The as-synthesized coconut shell was burned to be a charcoal named as HC-A. The charcoal was further proceeded by heating using a furnace with the temperature of 1000°C named as HC-B. Commercial hard carbon named as HC-C was also prepared to compare the quality of samples. The specific capacitance obtained from cyclic voltammetry test of sample HC-A, HC-B, and HC-C with a scan rate of 25 mV/s are 6.73×10-3 F/g, 1.10×10-3 F/g and 4.09×10-3 F/g, respectively. The Na+ ion diffusion coefficient of sample HC-A, HC-B and HC-C obtained from electrochemical impedance spectroscopy test are 5.75 ×10-15cm2s-1, 2.85 ×10-15cm2s-1, and 1.78×10-15cm2s-1. The results display that carbon material from coconut shell and hard carbon commercial have comparable value indicating by the same order of electrochemical quantity. This comprehensive study provides a feasible method and opens new opportunities for biomass carbon, and extends the strategy to design the high-performance anode materials for batteries.