Enhanced Electrochemical Performance of Aqueous Zinc‐Ion Batteries With Porous Basil‐Derived Carbon and Nanostructured MnO<sub>2</sub> Composite Cathodes
Yuda Prima Hardianto, Abdulmajid A. Mirghni, Syed Shaheen Shah, Haneen Mohammed Alhassan, Mostafa M. Mohamed, Bashir Ahmed Johan, Ananda Sholeh Rifky Hakim, Md. Abdul Aziz
Abstract
ABSTRACT This study introduces a novel composite cathode for aqueous zinc‐ion batteries (ZIBs), leveraging porous basil‐derived activated carbon (BAC) and nanostructured manganese dioxide (MnO 2 ) synthesized through a one‐step hydrothermal process. For the first time, basil‐derived carbon is integrated with MnO 2 , resulting in enhanced electrochemical performance. The MnO 2 /BAC composite delivers a remarkable specific capacity of 237 mAh/g at 0.5 A/g, along with an energy density of 314 Wh/kg and a power density of 0.66 kW/kg, outperforming cathodes made from pristine MnO 2 or BAC. These improvements stem from reduced particle size and a synergistic balance of capacitive and diffusive charge storage mechanisms. Density functional theory calculations corroborate the experimental results, revealing the composite's superior quantum capacity (158.7 µC/cm 2 ) and quantum capacitance (80.4 µF/cm 2 ). Stability assessments highlight excellent cycle life, with > 90% capacity retention and 100% Coulombic efficiency over 300 cycles. The exceptional performance is attributed to the material's unique nanostructure, high surface area (1090 m 2 /g), and optimized porosity. Additionally, practical applications of ZIBs in pouch cell form using the MnO₂/BAC cathode are demonstrated, showcasing its capability to power a toy car over a satisfactory distance. This study establishes a new benchmark for sustainable and cost‐effective cathode materials, significantly advancing ZIB technology for high‐efficiency energy storage applications.