Composition and thermoelectric power factor variation of (Bi2Te3)0.96(Bi2Se3)0.04 crystal in growth direction

(Bi2Te3)0.96(Bi2Se3)0.04 crystal, which is an n-type thermoelectric semiconductor, has many applications in thermoelectric cooling systems. Single crystal of this composition was grown by Traveling Heater Method. A sensible gradient in thermoelectric power factor was observed in the first quarter length of the prepared crystalline ingot. Characterizing the crystallization procedure and ingot composition, the gradient was attributed to the variation of the Bi2Se3 concentration of Bi2Te3–Bi2Se3 quasi-binary solid solution system. The structural properties were characterized by means of XRD analyses. Results of composition variation (Bi2Se3 distribution function) were in good correlation with experimental thermoelectric power factor measured along the grown rod.