3D Controlled Growth of Binder-Free Manganese Ferrite Electrodes for High-Performance Hybrid Supercapacitor Device

The remarkable electrochemical features and promise for improved performance of binder-free manganese ferrite have attracted a lot of research interest in hybrid energy storage devices. The fine-tuning of preparative parameters has a significant impact on energy-storing performance, with deposition time appearing as a crucial parameter in enhancing their electrochemical properties. This work offers a simple and scalable method for the preparation of manganese ferrite with varying deposition times using chemical bath deposition (CBD). Varying deposition time results in a transformation from the manganese ferrite hydrate (MnFe₂O₄.H₂O) to manganese ferrite (MnFe₂O₄) cubic structure and alteration in morphology from tetrahedral crystals to octahedral-like in MnFe₂O₄ series thin films (C-MFO). The MnFe₂O₄ electrode with an optimal deposition time of 7 h (C-MFO3) sample, featuring a cube-like morphology, achieves a maximum specific capacitance (Cs) of 491.2 F g⁻¹ at 1.5 A g⁻¹, maintaining 81.1% retention. Furthermore, the constructed hybrid supercapacitor device (HSD) exhibits a high Cs of 73.3 F g⁻¹, along with a specific energy (SE) of 36.7 Wh kg⁻¹ at a specific power (SP) of 1.7 kW kg⁻¹. This work introduces a scalable method for producing binder-free manganese ferrite electrodes, suitable for use as cathodes in hybrid energy storage devices for practical applications.