Manganese based electrodes in alkaline and neutral electrolytes for flexible energy storage devices

Flexible electrodes have been researched for e-textile. Screens have been produced as flexible and commercially are available. However, flexible energy storage and conversion devices have not been produced and commercialised. The motivation of this study is to fabricate flexible electrodes for energy storage and conversion devices. The research focuses on the electrodeposition of manganese onto graphite substrates using deep eutectic solvents (DESs). The study aims to optimize electrode conditions (growth and cycling) to achieve electrodes with high electrochemical stability, extensive active surface coverage, and enhanced areal capacitance. The experimental approach involves the preparation of electrode from Ethaline solutions having MnCl2 by applying various potentials (-1.5 V, -2.0 V, and -2.5 V) for 500 seconds. The electrodes are then characterized using techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Electrochemical properties are assessed through cyclic voltammetry in 1 M KOH and 1 M Na2SO4 electrolytes for fuel cell and supercapacitor applications. The resulting coatings were not suitable for hydrogen evolution in alkaline electrolyte. The findings reveal that lower deposition potentials (more negative voltage) lead to a denser manganese layer and higher potentials (less negative potential) could cause thinner film. The thinner films resulted in higher specific capacitance and electrochemical performance because ions could have high flux on coating. The study contributes to the field of energy storage devices by demonstrating the potential of manganese-coated graphite electrodes in alkaline and neutral media for flexible supercapacitor applications, offering a promising alternative to expensive materials.