TY - JOUR T1 - Effect of annealing and potassium substitution on the thermoelectric and magnetic properties of directionally grown Bi2Sr2Co2Oy ceramics JO - Boletín de la Sociedad Española de Cerámica y Vidrio T2 - AU - Çetin,Gizem AU - Özçelik,Bekir AU - Gürsul,Mehmet AU - Torres,Miguel Angel AU - Madre,Maria A. AU - Sotelo,Andres SN - 03663175 M3 - 10.1016/j.bsecv.2019.08.004 DO - 10.1016/j.bsecv.2019.08.004 UR - https://www.elsevier.es/en-revista-boletin-sociedad-espanola-ceramica-vidrio-26-articulo-effect-annealing-potassium-substitution-on-S0366317519300688 AB - Bi2Sr2−xKxCo2Oy (x=0.0, 0.025, 0.050, 0.075, 0.100, 0.125, and 0.15) ceramic materials have been fabricated using a classical ceramic process, followed by texturing through directional solidification. SEM analysis of samples, before and after annealing has shown that grains were aligned along the growth direction. While as-grown samples have several phases, besides the thermoelectric one, the annealed ones show much higher thermoelectric phase content. In addition, K-substitution increases the thermoelectric phase content and enhances grain orientation. These improvements decrease the electrical resistivity without significant changes in Seebeck coefficient. The maximum power factor value for 0.10K-substituted annealed samples has been found as 0.20mW/K2m. This is superior to the highest reported for hot-pressed materials. However, all samples have similar magnetic properties. ER -