Fe3C and Fe3O4 decorated porous carbon as high volumetric capacitance/rate electrodes for supercapacitor

Abstract

As the most attractive electrode for supercapacitors, renewable carbon-based material exhibits slow charge and discharge ability and low volumetric energy density, severely hindering its extended applications. Herein, a neotype and high-performance carbon-based nanocomposites were successfully prepared from Linum usitatissimum. L stems assisted with K4Fe(CN)6·3H2O through a green and straightforward high-temperature treatment method. Benefiting from the activation and decomposition of K4Fe(CN)6·3H2O, the carbon-based nanocomposite decorated by Fe3C and Fe3O4 possesses moderate porous volume, heteroatoms content, and graphitization degree. These characteristics endow the supercapacitor assembled from as-prepared carbon-based nanocomposite with fast charge/discharge ability, high volumetric capacitance (303.8 F cm−3, 1 A g−1), excellent rate performance (61.3%, 100 A g−1), and outstanding cycle life. Owing to abundant N/O-containing functional groups, high C=C content, and appropriate specific surface area, the resultant nanocomposite also exhibits excellent organic dye removal performance. Overall, this work offers a green and efficient avenue for designing multi-doped carbon-based nanocomposites in electrochemical energy storage and organic dye removal.