Design And Preparation Of Nanomaterials With Electrochemical Storage Properties

The demand for energy storage makes it imminent to search sustainable energy-storage materials.Manganese oxide,as a kind of transition metal oxides,shows excellent performance in the field of electrochemical storage.In this dissertation,a variety of nanomaterials,such as trimanganese tetraoxide/reduced graphene oxide nanocomposites,birnessites intercalated with different cations and trimanganese tetraoxide nanowires were prepared via facile solution-phase methods.The structure,morphology and chemical composition of the prepared nanomaterials were characterized by various measurements including X-ray diffraction,scanning electron microscopy,transmission electron microscopy and X-ray photoelectron spectroscopy.Results showed that the introduction of graphene has a certain effect on the morphology of trimanganese tetraoxide nanomaterials,the birnessites intercalated with different cations have similar lamellar globular morphology,and the as-prepared trimanganese tetraoxide nanowires have single crystal structure with smooth edges.In addition,the as-prepared nanomaterials were utilized as positive materials to assemble the asymmetric supercapacitors,of which the electrochemical storage properties were investigated by cyclic voltammetry,galvanostatic charge-discharge test,cycling stability test and electrochemical impedance spectroscopy.The results showed that the as-prepared materials exhibit excellent electrochemical storage performance and possess great application prospects in energy storage devices.