<![CDATA[Fe3O4 nanoparticles are one of the materials that can be used as a battery anode. However, this material is prone to agglomeration, which hinders the insertion and extraction of sodium ions. An alternative solution in the form of Mn doping on the Fe3O4 material can help stabilize the structure, thereby improving the sodium-ion diffusion rate. A Mn0.25Fe2.75O4/rGO nanocomposite was successfully fabricated via the physical blending method. Characterization of the Mn0.25Fe2.75O4/rGO sample was carried out using XRD and FTIR instruments to determine the sample’s structure and functional groups, respectively. The XRD results show that the particle size of Mn0.25Fe2.75O4/rGO is approximately 12.80 nm. The FTIR test results for Mn0.25Fe2.75O4/rGO show Mn-O and Fe-O (M-O) vibration bonds at wavenumbers of 635.10 cm⁻¹ and 568.47 cm⁻¹, respectively, which represent manganese ferrite bonds. Meanwhile, rGO bonds were detected from the C-OH and C-O-C group vibrations at wavenumbers of 1205.00 cm⁻¹ and 1034.88 cm⁻¹, respectively. Electrochemical testing of the sodium-ion battery based on the Mn0.25Fe2.75O4/rGO anode was successfully carried out using CV, GCD, and EIS. The CV characterization results show sodium-ion battery capacitance values based on the Mn0.25Fe2.75O4/rGO anode of 29.2, 18.4, 12, 8.4, 6.7, 5.6, and 4.7, respectively, for scan rates of 1, 5, 10, 15, 20, 25, and 30 mV/s. The EIS characterization results yielded series resistance (Rs), charge transfer resistance (Rct), and Warburg resistance values for the sodium-ion battery based on the Mn0.25Fe2.75O4/rGO anode of 100, 250, and 2.1 Ohm, respectively. These results indicate that the Mn0.25Fe2.75O4/rGO-based anode has potential as a base material for sodium-ion battery anodes.]]>
