Nipa palm shell-derived magnetic carbon aerogel for absorbents and storage energy

At this time, multi-application materials are developing to match the trend of green sustainable energy development . And with characteristics acting as high porosity, light weight, bulk form with diverse pores, and high chemical compatibility, metal-doped carbon aerogel becomes a potential material. In this study, Fe-doped carbon aerogel with crosslinking sodium alginate (Fe-SA-CA) was synthesized through a simple process of freeze-drying, aerogel pyrolysis, and pyrolysis temperatures (600–800 °C) were investigated to find suitable materials for adsorption and electrochemical applications. The characteristics of the material are analyzed by modern methods, proving that the surface of the material has a variety of pores with a size approximately 2 nm, and has the main components including C, O, and Fe. Fe-SA-CA shows potential for adsorption of oils, organic solvents, and crystal violet pigments. In particular, electrochemical properties of Fe-SA-CA are determined through cyclic voltammetry, galvanostatic charge discharge, and electrochemical impedence spectroscopy, to obtain high specific capacitance (203 F/g at 50 mV/s), constant discharge capacity over 500 cycles. Futhermore, thanks to the presence of the element Fe, the magnetic material is easily recovered with a magnet after used. In addition, the precursor used in the study is cellulose from nipa coconut shells - a large amount of biomass waste in Vietnam, thereby reducing production costs, limiting chemicals, and expanding the potential application of the Fe-doped carbon aerogel.