Cobalt-Doped Manganese Dioxide Hierarchical Nanostructures for Enhancing Pseudocapacitive Properties

Herein, overall improvement in the electrochemical performance of manganese dioxide is achieved through fine-tuning the microstructure of partially Co-doped manganese dioxide nanomaterial using facile hydrothermal method with precise control of preparative parameters. The structural investigation exhibits formation of a multiphase compound accompanied by controlled reflections of alpha-MnO2 as well as gamma-MnO2 crystalline phases. The morphological examination manifests the presence of MnO, nanowires having a width of 70-80 nm and a length of several microns. The Co-doped manganese dioxide electrode displayed a particular capacitive behavior along with a rising order of capacitance concerning with increased cobalt ion concentration suitable for certain limits. The value of specific capacitance achieved by a 5% Co-doped manganese dioxide sample was 1050 F g(-1) at 0.5 A g(-1), which was nearly threefold greater than that achieved by a bare manganese dioxide electrode. Furthermore, Co-doped manganese dioxide nanocomposite electrode exhibits exceptional capacitance retention (92.7%) till 10,000 cycles. It shows the good cyclability as well as stability of the material. Furthermore, we have demonstrated the solid-state supercapacitor with good energy and power density.

Automated summary

By fine-tuning the microstructure of partially Co-doped manganese dioxide nanomaterial using a facile hydrothermal method, overall improvement in the electrochemical performance is achieved, particularly in terms of increased capacitance at certain cobalt ion concentrations. Additionally, the Co-doped manganese dioxide electrode exhibits exceptional capacitance retention, over 92.7% after 10,000 cycles, demonstrating good cyclability and stability.