SINTESIS DAN KARAKTERISASI MATERIAL TERMOELEKTRIK PEROVSKITE GANDA SR2TICO1-XFEXO6 (X = 0; 0,5; DAN 1)

• Main Author: Jeremia, Gilroy
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/75514
• Institution: Institut Teknologi Bandung

Research on thermoelectric materials is actively progressing in order to harness the wasted heat into usable electrical energy. In order to increase its efficiency, studies were carried out by means of doping, alloying, and nanostructuring. The effectiveness of the thermoelectric material depends on the Seebeck coefficient, electrical and thermal conductivity, as well as the thermal stability of the material. To improve these thermoelectric properties, a high Seebeck coefficient and electrical conductivity, along with a low thermal conductivity value are required. Perovskite SrTiO3 which is an insulator with a high dielectric constant, but with substitution on Sr or Ti site, its thermoelectric properties can be enhanced. Here, the Ti site of the perovskite are substituted with Fe and Co to form+ a double perovskite structure of Sr2TiCo1-xFexO6 (with x = 0, 0.5, and 1). The double perovskites were then studied to learn about its properties which affected by the composition of Fe and Co as well as their sintering time. X-ray diffraction result for the 24-hour-sintered samples showed 2 phases for every variation of Co/Fe composition. Rietveld refinement of the XRD shows that those phases are Ti-rich and Co/Fe-rich phases. The lattice parameter for the Ti-rich phase in the x = 0 sample (STCO) decreases as sintering time increases. While for both phases of the x = 0.5 (STCFO) sample, the lattice parameters do not show significant changes when the sintering time was increased. For the Fe-rich phase of sample with x = 1 (STFO), its lattice parameter increases as the sintering time increases. DC conductivity (?DC) determination were conducted from the dielectric measurement. At the same temperature, 24-hour-sintered STFO has the highest ?DC compared to other samples with the same sintering time, while STCO has the lowest ?DC. At 300 K, the ?DC for STCO, STCFO, and STFO samples are 7,7258 × 10?8 S/m, 1,0184 × 10?4 S/m, dan 3, 2722 × 10?4 S/m, respectively. Thus, it is concluded that ?????? increases as Fe increases in the Sr2TiCo1-xFexO6.