Thermoelectric and mechanical properties of Bi_0.42Sb_1.58Te₃/SnO₂ bulk composites with controllable ZT peak for power generation

Bi2Te3-based materials' potential for power generation at lower to moderate temperatures is curtailed by intrinsic excitation. This study seeks to address this issue. This is accomplished by fabricating bulk thermoelectric materials consisting of varying weights of SnO2 via solid-state reaction and spark plasma sintering. Results show that the composite material has an average ZT value of similar to 0.85 in the 425-575 K temperature range. The lattice thermal conductivity of the composite material is reduced by approximately 54% compared to pure Bi0.42Sb1.58Te3 (BST) and almost 47% when compared to Cu1.8S modified- Bi0.42Sb1.58Te3 (m-BST) at 300 K. A high power factor is achieved, which almost doubled in the 425-575 K. The composite material also exhibits significantly enhanced hardness and modulus due to compositing. These findings provide a straightforward strategy for improving the low- to medium-temperature thermoelectric performance of commercial p-type (BiSb)(2)Te-3, which is crucial for expanding the temperature range of Bi2Te3-based materials.