Investigation of the Capacitive Properties of Bimetallic Iron–Nickel Organic Framework and Carbon Nanotube Composite on Carbon Felt Electrode

ABSTRACT The increasing global population and rapid depletion of energy resources have intensified the demand for renewable energy and advanced energy storage solutions. Supercapacitors, with their high power density, long cycle life, and fast charging capability, are emerging as a promising alternative to conventional batteries. This study reports, for the first time, the capacitive performance of a bimetallic FeNi metal‐organic framework (MOF) combined with multi‐walled carbon nanotubes (MWCNTs) on a carbon felt electrode. The composite was synthesized via a hydrothermal route and applied through a drop‐casting method. Electrochemical performance was evaluated using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge techniques. The resulting electrode demonstrated a specific capacitance of about 180 F/g over a wide current density range, nearly 100% coulombic efficiency, a power density up to 3600 W/kg, and an energy density of about 91 Wh/kg. Moreover, it retained 90% of its capacity after 700 charge–discharge cycles, underscoring its stability. These findings highlight the FeNi MOF‐MWCNT composite as a promising candidate for high‐performance supercapacitor electrodes.