Preparation and Characterization of Zinc Tungstate and Composite as Anode Material for Lithium-Ion Battery

Abstract

The thesis entitled “preparation and characterization of zinc tungstate and composite as anode material for lithium-ion battery” cover the preparation, characterization and electrochemical analysis as anode material for Lithium-ion battery (LIB) of zinc tungstate and their composites (ZnWO4/SnO2, ZnWO4/GeO2 and ZnWO4/SiO2) via solvothermal and microwave method. The structural, elemental and morphological properties of the prepared samples are characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX), high-resolution transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) measurements, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) techniques. Prepared ZnWO4 and ZnWO4@r-GO nanocomposite delivered initial discharge capacity of 746 and 1158 mAh g-1 respectively at current density of 100 mA g-1 and potential window 0.02 - 3 V versus Li/Li+ at room temperature. Further, ZnWO4/SnO2 and ZnWO4/GeO2 are tested as anode material for LIB. Increasing percentage of SnO2 increases the specific capacity of the ZnWO4/SnO2 composite and GO further boosts the specific capacity of the composite. The capacity of the first discharge curve of ZWSN-5, ZWSN-10 and ZWSN-10/GO nanocomposite is noticed as 882, 1316 and 1486 mAh g-1 respectively. While in the case of ZnWO4/GeO2, the initial discharge capacity of ZWGE5, ZWGE10 and ZWGEC nanocomposites were 761, 825, and 930 mAh g−1, respectively. Further, CNT boosts the performance of the ZnWO4/GeO2 composite. ZnWO4/SiO2 is prepared via microwave method and used as an anode material for LIB. The initial charge discharge capacity of the ZWSO5 nanocomposites is 570 and 314 mAh g-1 respectively at 10 mA g-1. The discharge capacity of the ZW, ZWSO1, ZWSO2, ZWSO3 and ZWSO4 are 145, 265, 278, 363 and 453 mAh g−1 respectively. The increasing amount of SiO2 in the ZnWO4/SiO2 composite increases the overall performance of the ZnWO4/SiO2 composite.