Graphene nanosheets (GNS) have garnered significant attention due to their exceptional properties and wide-ranging applications. This research aims to synthesize GNS from coconut shells and candlenut shells and to compare their performance in Fe ion adsorption and electrochemical properties. Both coconut and candlenut shells were used as raw materials, and the pyrolysis method was chosen to produce large-scale GNS. The GNS were characterized using Raman spectroscopy, X-ray diffraction, FTIR, FESEM-EDX, AAS, and electrochemical measurements, including CV and EIS on modified electrodes. New findings from this study reveal that GNS derived from candlenut shells exhibit thinner layers and fewer defects compared with those derived from coconut shells. This structural advantage contributes to superior Fe ion adsorption efficiency and better electrochemical performance, making the GNS from candlenut shells more suitable for applications in flexible electronics and electrochemical devices. Furthermore, the synthesis method effectively reduces the amount of oxides associated with defects in the GNS, enhancing the material's potential for high-performance applications. The GNS produced from candlenut shells showed an Fe adsorption effectiveness of 0.33 ± 0.012 mg/g, a charge transfer resistance of 0.78 kΩ, and a capacitance of 108.8 F/g, indicating their promising role in future technological applications.