Green synthesis of Ni-doped nipa palm shell-derived carbon aerogel for storage energy, electrochemical sensing, and oil adsorption

The development of the industry has increased the demand for energy storage, making the provision of energy storage devices essential. The supercapacitor is one of the potential energy storage devices, and carbon aerogel (CA) is a promising candidate for supercapacitor electrode fabrication. Ni-doped nipa palm shell-derived CA (Ni-NS-CA) was used to fabricate the electrode for supercapacitors to save production costs and utilize biomass wastes. Ni-NS-CA was synthesized via a three-step process: Hydrogel making through cross-linking (SA, Ni2+), freeze-drying, and pyrolysis. The characteristics of Ni-NS-CA are analyzed using a scanning electron microscope, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy, and Nitrogen adsorption–desorption isotherm 77 K. The electrochemical properties of Ni-NS-CA was analyzed via cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. With stable energy storage results (104.15 F g−1) and the electrochemical system based on Ni-NS-CA extends its application to Hg2+ sensing. Moreover, Ni-NS-CA was a potential material to solve oil spills, which has an oil adsorption capacity of 31.24 g g−1.