Morphology Control of Mixed Metallic Organic Framework for High‐Performance Hybrid Supercapacitors

Abstract The study presents the binder‐free synthesis of mixed metallic organic frameworks (MMOFs) supported on a ternary metal oxide (TMO) core as an innovative three‐dimensional (3D) approach to enhance electron transport and mass transfer during the electrochemical charge‐discharge process, resulting in high‐performance hybrid supercapacitors. The research demonstrates that the choice of organic linkers can be used to tailor the morphology of these MMOFs, thus optimizing their electrochemical efficiency. Specifically, a NiCo‐MOF@NiCoO 2 @Ni electrode, based on terephthalic linkers, exhibits highly ordered porosity and a vast internal surface area, achieving a maximum specific capacity of 2320 mC cm −2 , while maintaining excellent rate capability and cycle stability. With these performances, the hybrid supercapacitor (HSC) achieves a maximum specific capacitance of 424.6 mF cm −2 (specific capacity 653.8 mC cm −2 ) and 30.7 F cm −3 with energy density values of 10.1 mWh cm −3 at 167.4 mW cm −3 (139.8 µWh cm −2 at 2310 µW cm −2 ), which are higher than those of previously reported MMOFs based electrodes. This research introduces a novel approach for metal organic framework based HSC electrodes, diverging from the traditional emphasis on metal ions, in order to achieve the desired electrochemical performance.