Thermoelectric properties of some binary and ternary chalcogenides antimonides and ferrites

Abstract

Thermoelectric (TE) materials have drawn tremendous attraction nowadays because the thermoelectric effects facilitate direct conversion of thermal energy into electrical energy and vice-versa, for potential applications in waste heat recovery, power generation, refrigeration and so on. The brief introduction about thermoelectrics and their potential applications have been presented. The importance of thermoelectric parameters such as electrical conductivity (and#1048881;), Seebeck coefficient (S) and thermal conductivity (and#1049115;) are discussed. The salient features of familiar TE materials such as newlineChalcogenides, Zintl phases, Skutterudites, Clathrates, Half-Hausler intermetallics, thermoelectric oxides and nanostructured materials are also discussed. A variety of preparation and characterization methods of semiconducting materials and their basic principles and working aspects are also presented. The preparation of Co2.0Sb1.6Se2.4 and Co2.0Sb1.5M0.1Se2.4 (M=Zn, Sn) compounds by using vacuum sealed tube melting reaction method and their thermoelectric characterization are described. In recent years, Sb based chalcogenides have been widely studied due to their excellent TE newlineperformance. Hence, the present work focuses on preparation, crystal structure determination and thermoelectric studies of new Co-Sb-Se ternary system. The needle shaped single crystal specimens of Co-Sb-Se phase were subjected to single crystal diffraction studies to determine the crystal structure. The refinement of crystal data reveals that the material adopts FeAs2 type orthorhombic structure [Marcasite, space group Pnnm, a = 4.9864(3) Å b = 5.9657(3) Å c = 3.6933(2) Å]. newline newline