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Graphite has been employed as an energy storage material due to its ion intercalation capability. Nevertheless, the application of graphite in supercapacitors has been limited due to its strong bonding nature formed by sp2‐hydridized C─C. Herein, structural rearrangement of expanded graphite (EG) was achieved through planetary ball milling method. High‐levels of compressive and shear forces during milling not only rearranged the graphene stacks in the direction parallel to (002) plane but also developed a three‐dimensional (3D) graphite structure with (101) crystallinity. This crystallographic rearrangement of milled EG (MEG) restores electrically conductive sp2‐domains and regenerates intra‐ and interparticle electron transfer pathways. Furthermore, MEG revealed a highly porous structure with enhanced microporosity, balancing the macro‐, meso‐, and micropore ratio. The synergy of morphological and crystallographic rearrangements in MEG enhances the simultaneous ion and electron transport kinetics for electric double layer formation, making it suitable for ultrafast electric double layer capacitor electrodes (80 F/g at 50 A/g). [ABSTRACT FROM AUTHOR]

The catalytic activity of metal cations exchanged with heteropoly acids (HPA) and the selectivity towards precursor composite materials can be tailored by adjusting the reaction mechanism. A structural defect engineering strategy was developed for the metallic phase of O-MoS2, doped with a Keggin-type HPA to serve as a double gyroid layer (O-MoS2@HPA). This was achieved through thermal oxidation treatment to enable a high surface area by depositing abundant catalytically active sites on the graphite felt. Optimization strategies involving MoO3−x (MoO3−x@K3PW12O40) species have been crafted, anchoring active sites in a spherical nanomorphology through the self-assembly of acid. This development introduces a new approach for enhancing electrocatalysts, aiming for superior performance in VRFB. The electrochemical results show remarkable enhancement in electrocatalytic behavior with abundant heteroatom active sites, promoting oxidation at a high current density of 150 mA/cm2, achieving an outstanding 84.62% high energy efficiency. This result is 14% higher than pristine graphite felt and exhibits extraordinary stability after 1350 cycles, overcoming the sluggish kinetic mechanism that limits redox active materials. This study creates new avenues for the design of hybrid micro/nanostructured materials on cathodes and anodes to achieve excellent performance as electrocatalysts for VRFB. [ABSTRACT FROM AUTHOR]