Πλοήγηση ανά Συγγραφέας "Vernardou, Dimitra"

Τώρα δείχνει 1 - 2 of 2
  • Μικρογραφία εικόνας
    Τεκμήριο
    Evaluation of APCVD V2O5 for energy storage applications
    (ΕΛΜΕΠΑ, Σχολή Μηχανικών (ΣΜΗΧ), ΔΠΜΣ Νανοτεχνολογία για Ενεργειακές Εφαρμογές, 2024-07-08) Zogalis, Aristeidis-Konstantinos; Ζώγαλης, Αριστείδης-Κωνσταντίνος; Vernardou, Dimitra; Remediakis, Ioannis; Βερνάρδου, Δήμητρα; Ρεμεδιάκης, Ιωάννης
    My thesis revolves around the preparation, characterisation and then evaluation of thin films of Vanadium Pentoxide in three Electrolytes. These films were on a glass substrate with a thin FTO (Fluorine doped Tin Oxide) film, our precursor being Vanadium Acetylacetonate (ACAC). The method used to create our samples was APCVD (Atmospheric Pressure Chemical Vapour Deposition). Each sample was characterised using Raman Spectroscopy, Energy Dispersive Spectroscopy (EDS), Scanning Electron Microscope (SEM) and X-ray photo electron spectroscopy (XPS). The evaluation was performed through Cyclic Voltammetry, where we observed the behaviour of our samples in each separate electrolyte, namely Lithium, Aluminium and Zinc. Additionally, there is a guide to install GPAW, a simulation program that uses DFT theory which could assist in predicting and thus “perfecting” our experimental model to yield more favourable results. Finally, we of course discuss our findings and provide some advice moving forward
  • Μικρογραφία εικόνας
    Τεκμήριο
    Exploring the growth mechanism of the electrodeposited carbon components as potential buffer layers for energy storage applications
    (ΕΛΜΕΠΑ, Σχολή Μηχανικών (ΣΜΗΧ), ΔΠΜΣ Νανοτεχνολογία για Ενεργειακές Εφαρμογές, 2024-07-09) Apostolopoulou, Maria; Αποστολοπούλου, Μαρία; Vernardou, Dimitra; Βερνάρδου, Δήμητρα
    In recent years, the depletion of fossil fuels and environmental pollution has prompted both industry and the scientific community to seek alternative energy sources. Lithium-ion batteries, due to their high energy density, small size, long lifetime and low pollution, have gained a dominant position in everyday life, finding application in portable devices (laptops, smart phones), power tools and electric vehicles. Due to this rapid development of technology, there is growing demand for more efficient energy storage devices. This dissertation aims to investigate carbon-based materials, especially graphene oxide as a potential buffer layer for electrodes in lithium-ion batteries (LIBs) and electrochemical capacitors (ECs). The unique properties of carbon-based materials, such as high surface area, excellent electrical conductivity and tunable pore structures, have led to their widespread application as alternative materials to traditional graphite. The material synthesis procedure was carried out using a graphene oxide dispersion solution, which was prepared by the modified Hummer method. The dispersed solution was the electrolyte in the electrodeposition technique for the immobilization of graphene oxide on copper substrate. The growth mechanism of the material was studied for different deposition time and current. Additionally, the impact of the electrolyte concentration (Li2SO4) and the amount of graphene oxide on the electrochemical behavior of the synthesized materials was investigated. Then, the stability of the optimum material obtained (i.e. highest current and material’s adhesion) was tested in 600 continuous charge/discharge cycles with sufficiently satisfactory results. In all samples, structural, morphological and electrochemical measurements were carried out by Raman spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). In conclusion, the dissertation highlights the potential of graphene oxide synthesized via the electrodeposition technique as a cost-effective, rapid, and promising buffer layer for anode materials in energy storage devices.