Waste-Derived Heteroatom-Doped Activated Carbon/Manganese Dioxide Trio-Composite for Supercapacitor Applications

The utilization of biological-waste materials to synthesize heteroatom-doped activated carbon (AC), followed by metal oxide functionalization for high-performance supercapacitors is described. Herein, easily available and cheap biowaste, i.e., cow dung (CD), and low priced-nontoxic waste melamine sponge (MS) are consumed to produce nitrogen-doped AC followed by functionalization with economically inexpensive manganese dioxide (MnO₂), that is utilized to provide an efficient energy-storage material. The use of CD, MS, and MnO₂ materials furnishes the process with sustainability, cost-effectiveness, and safe components for the doping of heteroatoms and metal oxide on the carbon framework for energy-storage applications. The subsequent material exhibits maximum specific capacitance, i.e., 424 F g⁻¹, at a current density of 1 A g⁻¹, which relates to maximum power as well as the energy density of 1817 W kg⁻¹ and 47.7 Wh kg⁻¹, respectively. The resultant material shows high-performance specific capacitance and excellent cyclic stability for supercapacitor applications. This modest process of the direct production of N-doped AC followed by MnO₂ functionalization is a simple, economical, large production of a nanomaterial prototype for different applications including supercapacitor applications.