PHYSICAL MECHANISMS OF ELECTRICAL AND THERMOELECTRIC PROPERTY MODIFICATION IN Ce- AND Yb-DOPED Bi₂Te₃

Abstract

Thermoelectric materials are very important for lots of uses. Bismuth telluride or Bi₂Te₃ is a choice for things that work around room temperature. This is because Bi₂Te₃ has a Seebeck coefficient it can carry electricity well and it does not carry heat well.To make Bi₂Te₃-based materials work better for uses adding rare-earth elements to them is a good idea. In our study we looked at how adding Ce and Yb to Bi₂Te₃ affects its properties. We checked how the added atoms change the number of charge carriers how fast they move how they scatter phonons how well they carry electricity the Seebeck coefficient, how well they carry heat, the power factor and the thermoelectric figure of merit ZT of Bi₂Te₃.The results show that adding rare-earth elements like Ce and Yb can change the structure and defect state of Bi₂Te₃. This affects how charge carriers move and how heat is transferred in Bi₂Te₃.It is interesting that cerium and ytterbium have different effects on the thermoelectric properties of Bi₂Te₃. This is because they have different atomic masses, ionic states and ways they interact with the Bi₂Te₃ crystal lattice.This study shows how important it is to choose the type and amount of added elements to improve the efficiency of Bi₂Te₃-based thermoelectric materials. By understanding how elements like Ce and Yb interact with Bi₂Te₃ we can create efficient thermoelectric materials for many uses. This can lead to developments in many fields.The way added elements interact with Bi₂Te₃ is complicated. More research is needed to understand what is really going on. However our study shows that adding rare-earth elements can improve the performance of Bi₂Te₃-based materials.As research continues to learn more about these materials we can expect to see them get better and be used in ways. Overall developing materials is crucial for many industries. Our study helps to improve the performance of Bi₂Te₃-based materials.By looking at how elements like Ce and Yb affect Bi₂Te₃ and how they interact with it we can create efficient and effective thermoelectric materials. These materials can be used for things like getting energy, from heat or cooling systems.