The synthesis, characterization and electrochemical performance of hollow sandwich microtubules composed of ultrathin Co3O4 nanosheets and porous carbon using a bio-template

Biomorphic 2D Co3O4 nanosheets/mesoporous carbon microtube composites are solvothermally prepared and subsequently calcined using ramie as a biotemplate. The as-prepared composites are fabricated using two sides of Co3O4 nanosheets (NSs) supported on porous carbon microtubes and exhibit a unique tubular morphology and porous features. The present biomorphic materials show a specific capacitance of 1280.6 F g−1 at 1 A g−1, and outstanding charge–discharge cycle stability with a capacitance retention of 96.89% after 15 000 cycles. The remarkable pseudocapacitive performance and cyclability are attributed to the unique microstructure, the high specific surface area and the optimized hierarchical microstructure inherited from the biotemplate.