Biomorphic Mn₃O₄ nanocrystal/porous carbon microfiber composites were hydrothermally fabricated and subsequently calcined using cotton as a biotemplate. The as-prepared material exhibited a specific capacitance of 140.8 F·g-1 at 0.25 A·g-1 and an excellent cycle stability with a capacitance retention of 90.34% after 5000 cycles at 1 A·g-1. These characteristics were attributed to the introduction of carbon fiber, the high specific surface area, and the optimized microstructure inherited from the biomaterial.
Keywords: MnO2; biotemplate; carbon microfibers; electrochemical properties; energy storage and conversion; microstructure.