The Study of Mn2O3 As a Cathode Material for Zinc-Ion Batteries

Abstract

Energy and the environment are two of the most critical problems related to human survival and development in society. The ever-increasing demands [1] for energy have led to increasing development of alternative energy systems, such as wind, solar, tidal, and geothermal. These systems are intermittent and require suitable means of energy storage. Among available storage choices, electrochemical methods, such as batteries, are competitive in terms of specific energy, flexibility, and scalability. Aqueous zinc-ion batteries (ZIBs) are receiving increasing interest due to their low cost, safe operation, and reasonable efficiency.Manganese is one of the most abundant metallic elements on earth. Manganese oxide is widely used in various industries, for applications such as deoxidization and desulfurization, catalysis, and batteries, due to the different oxidation states (2+, 3+, and 4+) of manganese. For battery electrode materials, the diversity of manganese oxide compositions and crystal structures make it attractive [2,3]. Manganese (4+) oxide (MnO2) has been widely used as the cathode material in ZIBs. Other oxides with different valence states, such as Mn3O4 (2+/3+) and Mn2O3 (3+), are possible cathode candidates.In this work, high-crystalline, nanosize Mn2O3 powder is synthesized via a precipitation and calcination method for utilization as the cathode in ZIBs. The cathode is fabricated by producing a slurry of the Mn2O3 powder, carbon black (conductive agent) and polyvinylidene fluoride (PVDF, binder), and applying as a paste to a porous carbon substrate. The resultant electrodes are characterized using electrochemical techniques (e.g., cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) method) and microstructural methods (e.g., scanning electron microscopy (SEM) and x-ray diffraction (XRD)) to determine the mechanisms associated with charge and discharge. Battery cycling tests are also performed using zinc foil as the anode and compared with previous studies of Mn2O3 electrodes [4,5]. A specific capacity of 211 mAh/g is achieved after 200 cycles at a current density of 500 mA/g. Also, 70% capacity retention can be reached after 1100 cycles at a current density of 2000 mA/g. Dincer, I. Renewable Energy and Sustainable Development: a Crucial Review. Renewable and Sustainable Energy Reviews 2000, 4(2), 157–175.Ingale, N. D.; Gallaway, J. W.; Nyce, M.; Couzis, A.; Banerjee, S. Rechargeability and Economic Aspects of Alkaline Zinc–Manganese Dioxide Cells for Electrical Storage and Load Leveling. Journal of Power Sources 2015, 276, 7–18.Song, M.; Tan, H.; Chao, D.; Fan, H. J. Recent Advances in Zn-Ion Batteries. Advanced Functional Materials 2018, 28 (41), 1802564.Jiang, B.; Xu, C.; Wu, C.; Dong, L.; Li, J.; Kang, F. Manganese Sesquioxide as Cathode Material for Multivalent Zinc Ion Battery with High Capacity and Long Cycle Life. Electrochimica Acta 2017, 229, 422–428.Mao, M.; Wu, X.; Hu, Y.; Yuan, Q.; He, Y.-B.; Kang, F. Charge Storage Mechanism of MOF-Derived Mn2O3 as High Performance Cathode of Aqueous Zinc-Ion Batteries. Journal of Energy Chemistry 2021, 52, 277–283.