From acorn to microporous carbon for sustainable sodium-ion battery

• Acorn is a promising low-cost source of carbon for the negative electrode of sodium-ion battery. • Latent pores help to enhance electrochemical capacity. • Enhancement of the electrochemical performance by selecting pyrolysis temperature, acid-treatment and electrolyte solution. To promote a sustainable economy, developing sodium-ion batteries with carbon electrodes derived from biomass can be advantageous. This study focuses on carbon prepared from acorn nuts through carbonization at temperatures ranging from 700 to 1000 °C. The method also involves treatment with sulfuric acid. The porosity of the carbon can be adjusted to optimize its electrochemical performance. To characterize the surface properties, both nitrogen adsorption and carbon dioxide adsorption methods are employed. The impact of latent (closed) pores and external (open) porosity on electrochemistry is also discussed, along with the use of various electrolyte solutions. The article emphasizes the tailoring of biomass-derived carbon for the development of sustainable batteries, particularly the porosity.