Biomass nanoarchitectonics with Annona reticulate flowers for mesoporous carbon impregnated on CeO2 nanogranular electrode for energy storage application

[Display omitted] •Biowaste derived mesoporous carbon impregnated on CeO2 nanogranular using a pyrolysis method followed by a co-precipitation method.•Mesoporous carbon prepared by pyrolysis at 800 °C shows a high surface area of 262.95 m2/g and 573.6F g−1 at 2 mA cm-2current density and excellent rate capability of 92.10 %.•The mesoporous carbon carbon impregnated on CeO2 nanogranular reveals a high specific capacitance of 753.2 % Fg−1 at 2 mA cm-2current density and an excellent rate capability of 95.50 %.•The outstanding outcomes of this work provide a method for the ecologically friendly and cost-effective development of energy storage systems. Metal oxide semiconductors with mesoporous nanoarchitecture are interesting new materials because they have more active sites and a substantially higher surface area, of making them useful for various applications. Herein, we report the mesoporous carbon impregnated on CeO2 nanogranular using a pyrolysis followed by a coprecipitation method. The ecological and affordable biowaste precursor, Annona reticulate flower, was used to prepare the mesoporous carbon. The effect of porous carbon in CeO2 nanogranular on the electrochemical properties of the mesoporous carbon impregnated on the CeO2 nanogranular electrode has been studied meticulously. A CeO2 electrode showed a specific capacitance of 332.9F g−1 at 2 mA cm−2 current density and an excellent rate capability of 88.23 %. Then mesoporous carbon reveals a specific capacitance of 573.6 F g−1 at 2 mA cm−2 current density and an excellent rate capability of 92.10 %. Furthermore, the composition of mesoporous carbon and CeO2 electrodes showed an enhancement in the supercapacitor behavior. It showed a high specific capacitance of 753.2 % Fg−1 at 2 mA cm−2 current density and an excellent rate capability of 95.50 %. It is observed that the specific capacitance of the composite electrode is higher than that of the individual electrode because the specific area and porosity of the composite electrode are increased, which helps to adsorb more electrolytes and increase the supercapacitor’s behavior. The findings show that composite electrodes made from mesoporous carbon generated from waste biomass and nanogranular CeO2 can be significant electrode materials for energy storage applications.