الفهرس 
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Abstract
Abstract
This thesis is an attempt to add tangible progress on a long road that began years ago to bring the magnesium battery to commercial use. By introducing rich perovskite structure material represented by barium titanate (BaTiO3) as a cathode, and examining a series of different electrolytes ranging from liquid to solid and binary. Work has been launched as follow:
1- Attempts to more understand about the nature of tetragonal structure of the ferroelectric BaTiO3 (BTO) at room temperature and phase transition by reaching the Curie temperature converting the structure into ideal cubic structure of paraelectric BTO. This carried out by a series of characteristic analyses for the cathode material as a pure, with magnesized and 150°C (over Curie temperature) heated-magnesized. These different cathodes are tested electrochemically by using liquid electrolyte synthesized from mixing Magnesium perchlorate [Mg(ClO4)2], and magnesium nitrate [Mg(NO3)26(H2O)] with Ethylene carbonate [(CH2O)2CO], revealing a clear specific capacity gab for the modified cathode with stable performance of the electrolyte.
2- Using an unconventional electrode, BTO, with replacing the conventional electrolyte by a dual layer of liquid and polymer electrolyte onto the cathode and anode respectively. We investigate the structure and electrochemical properties by a series of analysis and measurements. The quasi-solid-state Mg batteries fabricated with pre-magnesiation and thermal treated BTO cathode materials show good electrochemical performance. Dual electrolyte exhibits a remarkable Mg-ion conductivity up to 4.62x10-4 Scm-1 at 55°C, a high transfer number (𝑡Mg2+ = 0.74), low overpotential and stable Mg stripping/plating in the initial cycles. Furthermore, the cell based on the dual electrolyte with pre-magnesiation and thermally treated BTO cathodes delivered a high initial discharge capacity and stable cycling around 68 mAhg-1 for more than 15 cycles. The approaches herein may provide new directions for exploiting high-performance Mg batteries through the perovskite structure cathode and functional dual electrolyte.
3- Adding sulfur to BTO as a cathode investing its high theoretical capacity (1675mAhg-1), with adding succinonitrile (SN), to the liquid electrolyte showing the ability of SN to dissociate the salts for higher ionic conductivity with respect to traditional organic solvents. The optimum ratio of SN (2%) shows a lower stripping/plating overpotential with a transference number of 0.81. By using low cost and superfast microwave-assisted method synthesized the nano cathode m