Manganese oxides are of interest as, among a number of other applications, supercapacitor materials for energy storage systems. Nsutite, a naturally occurring Manganese Oxide was studied as a possible high-volume source of materials for supercapacitor applications. X-ray diffraction and thermal analysis (DSC/TGA) measurements were carried out to characterize its physical properties, and Cyclic Voltametry and galvanostatic charge-discharge measurements were carried out to obtain its electrochemical properties. The XRD and thermal results support transitions of nsutite, upon heating which were attributed to conversion to MnO2, and to Mn2O3 and eventually to Mn3O4. The electrochemical results of the as mined material show supercapacitance behaviour, suggesting that nsutite, with some heat processing, is to be a promising high-volume source of manganese oxides for supercapacitor applications.
References
[1]
Post, J.E. (1999) Manganese Oxide Minerals: Crystal Structures and Economic and Environmental Significance. PNAS, 96, 3447-3454.
[2]
Kim, H. and Popov, B.N. (2003) Synthesis and Characterization of MnO2-Based Mixed Oxides as Supercapacitors. Journal of The Electrochemical Society, 150, D56. https://doi.org/10.1149/1.1541675
[3]
Gambou-Bosca, A. and Belanger, D. (2016) Electrochemical Characterization of MnO2-Based Composite in the Presence of Salt-in-Water and Water-in-Salt Electrolytes as Electrode for Electrochemical Capacitors. Journal of Power Sources, 326, 595-603. https://doi.org/10.1016/j.jpowsour.2016.04.088
[4]
Mohammadi, N., Pourreza, K., Adeh, N.B. and Omidvar M. (2021) Defective Mesoporous Carbon/MnO2 Nano-composite as an Advanced Electrode Material for Supercapacitor Application. Journal of Alloys and Compounds, 883, Article ID: 160874. https://doi.org/10.1016/j.jallcom.2021.160874
[5]
Zhang, G.N., Zhang, J.H., Yang, H.J. and Li, X.F. (2022) In-Situ Redox Reaction Derived Porous Nanosheets of MnO2 for Supercapacitors. Materials Letters, 306, Article ID: 130858. https://doi.org/10.1016/j.matlet.2021.130858
[6]
Faulring, G.M. (1965) Unit Cell Determination and Thermal Transformations of Nsutite. The American Mineralogist, 50, 170-179.
[7]
Brousse, T., Belanger, D. and Long, J.W. (2015) To Be or Not to Be Pseudocapacitive? Journal of The Electrochemical Society, 162, A5185. https://doi.org/10.1149/2.0201505jes
[8]
Singhal, R., Fagnoni, J., Thorne, D., LeMaire, P.K., Martinez, X., Zhao, C., Gupta, R.K., Uhl, D., Scanley, E., Broadbridge, C.C. and Manivannan, M. (2019) Study of MnO2-Graphene Oxide Nanocomposites for Supercapacitor Applications. MRS Advances, 4, 777-782. https://doi.org/10.1557/adv.2019.86
[9]
Mohapatra, B.K., Nayak, B.R. and Sahoo, R.K. (1995) Characteristics of Nsutite (γ-MnO2) in Goriajhar Manganese Deposit, Gangpur Group, India. Journal of Mineralogy, Petrology and Economic Geology, 90, 280-287. https://doi.org/10.2465/ganko.90.280
[10]
Bish, D.L. and Post, J.E. (1989) Thermal Behavior of Complex, Tunnel-Structure Manganese Oxides. American Mineralogist, 74, 177-186.
