SYNTHESIS AND CHARACTERISATION OF CARBON DOT FOR ENERGY STORAGE

Carbon dots (CDs) have emerged as promising nonmaterial due to their potential in energy storage applications. This study aimed to synthesize and characterize carbon dots for energy storage using Raphia hookeri seeds. It presents the synthesis, characterization, and electrochemical evaluation of carbon dots (CDs) derived from Raphia hookeri seeds via a hydrothermal method. To achieve this, Raphia hookeri seeds were carbonized at 400 °C, 500 °C, and 600 °C, and the optimal precursor was selected based on visual fluorescence under a UV lamp. The synthesized CDs were characterized using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and UV-Visible Spectroscopy (UV-Vis). Electrochemical performance was assessed using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The sample carbonized at 600 °C showed a distinct yellowish-green emission, indicative of successful carbon dot formation. TEM and SEM revealed uniformly dispersed spherical particles with diameters below 10 nm. XRD patterns showed a broad peak around 20-26°, confirming their amorphous carbon nature. FTIR and EDX confirmed the presence of functional groups such as OH, C-O, and C-N, along with major elements including C, O, and Si. UV-Visible spectroscopy showed a maximum absorption at 231 nm with an absorbance of 1.2, indicating strong -transitions associated with CC bonds. Using Tauc plot analysis, the optical band gap was calculated as 3.3 eV, aligning with values reported for biomass-derived carbon dots. CV results exhibited broad redox features indicative of pseudocapacitive behavior. The Nyquist plot revealed a charge transfer resistance (Ret) of 12.5 1, and further analysis yielded a double-layer capacitance (C dl) of 1.53 µF and a relaxation time constant (r) of 1.92 us These findings demonstrate rapid charge transport and hybrid capacitive faradaic characteristics. In conclusion, the synthesized carbon dots from Raphia hookeri seeds possess favorable structural, optical, and electrochemical properties, establishing their promise as low-cost, eco-friendly materials for future energy storage technologies