Lead-Free High-Energy Density Thin Film Capacitors

The increasing demand for sustainable energy storage solutions necessitates the development of environmentally-friendly and reliable methods for the fabrication of energy storage devices. This thesis investigates the use of aqueous chemical solution deposition (CSD) for producing metal oxide electrodes and thin-film capacitors for energy storage applications. Aqueous CSD was used to prepare RuO₂ and LaNiO3 electrodes and to fabricate thin film capacitors based on Mn-substituted BaZrxTi1-xO3 (BZT), achieving excellent electrical properties, including high energy density, efficiency, and stability. The investigations identified the optimal composition of BZT thin films to have 15 at% Zr and demonstrated that the electrode size and architecture of the BZT thin film capacitors significantly influence their performance. The promising electrical results highlight the potential of aqueous CSD as a sustainable alternative to conventional organic solvent-based methods, providing a pathway for scalable and environmentally-friendly energy storage technologies.