The dielectric material SrTiO₃ (Strontium Titanate) is widely utilized in electronic circuits, microwave communications, magnetic sensors, energy converters, ferroelectric tiles, optoelectronic materials, oscillators, capacitors, filters, resonators, and more, due to its exceptional electrical properties. STO-based ceramics inherently offer numerous advantages, including low dielectric loss, high dielectric strength, and exceptional thermal-frequency stability. SrTiO₃, with its high dielectric constant (εr), is a promising material for supercapacitor applications. Despite extensive efforts to engineer the dielectric properties of this material, there is still room for further enhancement. The properties of SrTiO₃ are influenced by several factors, such as chemical composition purity, crystal structure, and the distribution of electric charges. This study focuses on the fabrication, examination, and analysis of the effects of varying synthesis parameters in the Spark Plasma Sintering (SPS) method on the material’s properties. The primary objective is to identify the optimal SPS parameters to achieve high-quality dielectrics. Precise control over the heating and cooling rates, sintering temperature, holding time, and applied pressure during the SPS process plays a critical role in grain formation, growth, and ultimately in determining the final dielectric properties of the material. Ten STO samples were fabricated and subjected to deoxygenation in a furnace. The structural properties were eva‎luated for phase identification, while the dielectric properties, including the measurement of dielectric constant (εr) with respect to temperature and frequency, and dielectric loss (D), electric polarization (P-E hysteresis loop), electrical resistivity, d₃₃ coefficient, and surface morphology were assessed using FE-SEM. XRD analysis confirmed the formation of the desired crystalline structure. The dielectric constant (εr) of the samples was measured at room temperature and up to 900°C. It was observed that the sample sintered at 1350°C for 10 minutes under an applied pressure of 30 MPa exhibited the best dielectric properties. The dielectric constant and dielectric loss of this material at 10 kHz were measured as 333 and 0.00076, respectively, which outperformed numerous studies reported in the literature. Results from other analyses supported these findings.

حميده شاكري پور

حسين احمدوند

جواد هاشمي فر , پرويز كاملي