Synthesis of activated carbons derived from avocado shells as cathode materials for lithium–sulfur batteries

Abstract

Novel mesoporous carbon cathode material for Lithium–Sulfur battery were successfully synthesized from the shells of the avocado fruit. The crystalline structure of the formed carbon was characterized via X-Ray diffraction whilst Scanning Electron Microscopy was used to observe the morphology. The electronic conductivity was determined as a function of pressure and the COOH functional group were quantified via a titration. The mesoporous structure of the formed carbon network allows for good sulfur penetration which is translated by decent electrochemical performance both in terms of cycle life and rate capability. Carbons prepared from waste avocado shells and functionalized with HNO3 offer a good performance in terms of capacity retention (500 mAh/g of sulfur after 100 cycles). This favorable performance may be attributed to the role of functional COOH groups on the surface of the activated carbon.