Bahtiyar, Doruk
For many years, materials in the form of metal sulfides, oxides, phosphates, and titanates have been developed as cathode and anode active materials to be used in energy storage devices. Borides and borates, recently, attracted the attention of researchers in this field. In this study, for the development of a new class of materials for energy storage applications, synthesis and characterization of metal (Fe, Mo, Mn, and V) borides and (Mn, and Y)borates were carried out. The obtained materials were tested for their activity in lithium-ion batteries. Chemical and structural analysis were performed using X-ray diffraction spectroscopy, and scanning electron microscopy. Electrochemical characterization of the cells showed that manganase boride has the highest initial specific capacity of 576.80 mAh/g while yittrium borate has a specific capacity of 78.54 mAh/g as lowest at 20 mA/g current density. After fifty cycles at 20 mA/g, capacity decrease was observed for all samples, capacity retention of VB was calculated as 85.37 % which was the highest among all samples that are synthesized during this study. Furthermore, cyclic voltammetry was applied to understand charge-discharge mechanism of samples. It was noted that all samples has SEı formation around 0.74 V.


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Electrochemical capacitors are the energy storage devices based mainly on electrical double layer formation. Their power densities are exceptionally high; however, their energy densities are characteristically low to compete various types of batteries in market. Therefore, there have been great amount of studies to enhance electrochemical capacitors’ energy density. Utilization of inorganic materials such as transition metal oxides and/or phosphides is one of the most common strategies to increase energy de...
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Özkaragöz, Nadire Nazlı; Dericioğlu, Arcan Fehmi; Department of Metallurgical and Materials Engineering (2022-2-08)
Ferroelectric materials are used in different applications because of their superior electrical and dielectric properties. Ferroelectric materials are polarized when an electrical field is applied to the material. This spontaneous polarization continues even if an electrical field is removed. BST (Barium Strontium Titanate) is one of the attractive ferroelectric materials which has a high dielectric constant and low dielectric loss tangent (tanδ). High dielectric constant and low loss tangent are necessary ...
Citation Formats
D. Bahtiyar, “DEVELOPMENT OF BORIDES/BORATES FOR ENERGY STORAGE DEVICES,” M.S. - Master of Science, Middle East Technical University, 2022.