We report the synthesis and electrochemical performance of a novel binary composite comprising rod-shaped α-phase 

Manganese dioxide (MnO₂) and pea-derived carbon (PDC) (MnO₂/PDC) for high-performance supercapacitors. The composite

was prepared by mechanical milling and characterized using XRD, FTIR, Raman spectroscopy, TEM, SEM, and 

XPS. The electrochemical evaluation in three- and two-electrode configurations with aqueous Na₂SO₄ electrolyte revealed 

good charge-storage capability, excellent rate performance, and superior cyclic stability. The synergistic combination 

of MnO₂ nanostructures with sustainable biomass-derived carbon significantly enhances electrochemical performance, 

offering a promising and environmentally friendly approach to next-generation energy-storage materials. The MnO2/PDC 

composite exhibited a specific capacitance of 303.4 F g−1  at a current density of 4 mA cm−2. Additionally, the MnO2/PDC 

composite demonstrated an excellent electrode material-electrolyte interface compatibility with capacitance retention rate 

of 90% after 5000 charge-discharge cycles. The composite attained a specific energy of 71.2 Wh kg−1 and a specific power 

of 1363 W kg−1. Moreover, the composite was tested in a two-electrode assembly device and it exhibited the specific 

capacitance of 107.7 F g−1 at 4 mA cm−2 current density.