Conversion of Salam leaves (Syzygium polyanthum (Wight) Walp.) bio-kitchen waste as functional activated carbon for sustainable supercapacitor electrodes

Abstract

Porous carbon based on bio/organic waste is a very popular raw material used in high-level applications due to its advantages of high porosity, high electrical conductivity, suitable pore structure, and good stability. In this study, bio-kitchen waste is used as a precursor to obtaining high functional activated carbon which is applied to electrochemical energy storage applications. This kitchen waste is focused on Salam leaves (Syzygium polyanthum (Wight) Walp.). Precursors are converted to porous carbon through a simple technique and a green approach without the addition of synthetic materials. In addition, activated carbon is designed in a new form of monolith without a binder. The material properties were thoroughly investigated through monolith dimension reduction and X-ray diffraction. The dimensions of the monolith are reviewed based on mass, thickness, and diameter. The activated carbon obtained shows porosity and amorphous properties which are useful in supporting its electrochemical natures. Furthermore, the electrochemical properties of carbon electrodes were reviewed using standard cyclic voltammetry and galvanostatic charge-discharge methods in a two-electrode system. In addition, a 1M H2SO4 aqueous electrolyte was selected to enhance the supercapacitor cell performance and it exhibit high specific capacitance of 145 F g−1. Based on these results, it is surprising that bio-kitchen waste has great potential as a high-carbon material for high-level applications.