Browsing by Author "Adoor, P."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Electrochemical performance and structural evolution of spray pyrolyzed Mn3O4 thin films in different aqueous electrolytes: effect of anions and cations
    (Royal Society of Chemistry, 2024) Adoor, P.; Hegde, S.S.; Badekai Ramachandra, B.R.; George, S.D.; Raviprakash, R.
    This work presents the impact of cycling in different cationic and anionic aqueous electrolytes on the electrochemical storage performance of the Mn3O4 thin film electrode prepared using the chemical pyrolysis method. Studies on the as-deposited electrode confirmed the formation of Mn3O4 phase. Extensive electrochemical analysis was performed using Na2SO4, NaCl, Li2SO4, K2SO4, and MgSO4 electrolytes to examine the influence of cations and anions on charge storage behaviour. Considerable changes were observed in the specific capacitances owing to different ionic sizes as well as hydrated ionic radius of the electrolyte ions. Accordingly, the electrode unveiled a good performance showing a specific capacitance of around 187 F g−1 at 0.5 A g−1 in K2SO4 electrolyte. Further, the electrode properties are examined after 500 CV cycles to trace the changes in the structural and morphological properties. X-ray diffraction (XRD) and Raman spectroscopic studies illustrate a partial phase transformation of electrodes from Mn3O4 to MnO2 irrespective of the electrolytes. These results are further corroborated with X-ray photoelectron spectroscopic (XPS) analysis where there was an increment in the oxidation state of manganese. It has been observed that the surface properties were significantly changed with cycling, as manifested by the wettability studies of the electrodes. The obtained results brings out the significance of electrolyte ions on the charge storage characteristics of Mn3O4 thin film electrodes in light of their possible application in electrochemical capacitors. © 2024 The Royal Society of Chemistry.
  • No Thumbnail Available
    Item
    Elucidating the Role of Copper-Induced Mixed Phases on the Electrochemical Performance of Mn-Based Thin-Film Electrodes
    (American Chemical Society, 2023) Adoor, P.; Hegde, S.S.; Badekai Ramachandra, B.R.; Sudhakar, S.N.; Raviprakash, R.
    Manganese oxide is a fascinating material for use as a thin-film electrode in supercapacitors. Herein, the consequences of copper incorporation on spray pyrolyzed manganese oxide thin films and their electrochemical performance were investigated. The Cu-incorporated manganese oxide thin films were deposited by spray pyrolysis, and their structural and electrochemical properties were thoroughly evaluated. The formation of the spinel Mn3O4 phase with effective Cu incorporation was confirmed by X-ray diffraction investigation. Through Raman studies, it was noticed that mixed phases of manganese oxide tend to form after Cu incorporation, and this result was also reflected in X-ray photoelectron spectroscopic studies. The surface morphology and roughness were also altered by the addition of copper. However, electrochemical measurements implied a reduction in the specific capacitance upon copper inclusion. The cyclic voltammetry test indicated a specific capacitance of 132 F/g for Mn3O4 electrodes, but a substantial drop for copper-incorporated samples due to the mixed manganese phase. The decremental tendency was further supported by galvanostatic charge-discharge studies and electrochemical impedance spectroscopic measurements. These results provide valuable insights into the effects of copper addition in manganese oxide thin-film-based electrodes for energy storage applications. © 2023 The Authors. Published by American Chemical Society