Crumpled Graphene Decorated with Manganese Ferrite Nanoparticles for Hydrogen Peroxide Sensing and Electrochemical Supercapacitors

Nanomaterials properties are deeply dependent on several features, being easily tuned according to its composition, shape, and dimensionality. Graphene, a two-dimensional (2D) material has outstanding properties that may be tailored by turning its shape to 3D conformations, similar to crumpled paper ball-like structures. Thus, some drawbacks related to graphene restacking could be avoided, besides enlightening a way to explore the properties of graphene-based materials. Herein, we synthesize crumpled graphene structures fully decorated by manganese ferrite (MnFe2O4) nanoparticles in one single step. The samples were produced using an aerosol-assisted capillary compression process and the crumpled paper-ball-like shape of the composites could be adjusted to incorporate increasing amounts of manganese ferrite nanoparticles. We explored two different applications for the obtained materials: as an electrochemical sensor for hydrogen peroxide, and electrochemical supercapacitors. As a proof-of-concept, we synthesized bare manganese ferrite and a composite of flat rGO:MnFe2O4, which assisted us to certify that the best performance is related to the synergistic effect between components, the ratio between them, and the proper shape of the composite.