From Waste to Energy Storage: Moderately Porous, N-doped Biochar from Microwave Pyrolysis of Watermelon Peel for Supercapacitor Applications

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@article{1714733,
      author = {Hafsat Nababa Abdulmumin, Muhammad Auwal Sa'ad , Sadiya Ahmad Muhammad },
      title = {From Waste to Energy Storage: Moderately Porous, N-doped Biochar from Microwave Pyrolysis of Watermelon Peel for Supercapacitor Applications},
      journal = {Iconic Research And Engineering Journals},
      year = {2026},
      volume = {9},
      number = {8},
      pages = {2066-2073},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1714733.pdf},
      abstract = {The microwave pyrolysis of watermelon peel at 250 °C yielded an extremely low solid residue (4.0 wt.%), indicating that the applied thermal conditions favored devolatilization rather than carbon conservation, making them suboptimal for targeted biochar production. Nonetheless, the resulting carbonaceous material exhibited a moderate specific surface area (~388 m² g⁻¹) and predominantly microporous structure with an average pore width of 1.64 nm, features favorable for charge storage. Its low pore volume (0.096 cm³ g⁻¹), however, limits immediate applicability as a high-capacitance electric double-layer capacitor (EDLC) electrode. To unlock its potential, post-synthesis activation—particularly chemical treatments to enhance surface area and pore volume while retaining nitrogen-derived heteroatom doping is recommended. Such optimization could introduce additional pseudocapacitance and broaden applicability to supercapacitors, adsorption, soil amendment, and catalysis. Overall, the study validates watermelon peel as a promising feedstock for functional porous carbons and highlights the need for process intensification and targeted activation to improve yield and electrochemical performance.},
      keywords = {Biomass, Pyrolysis, Microwaves. Biochar, Supercapacitor},
      month = {February},
      doi = {https://doi.org/10.64388/IREV9I8-1714733}
  }