Enhanced Thermoelectric Performance of p-Type Mg3–xZnxSb2/Sb Composites: The Role of ZnSb/Sb Composites

• DOI: 10.1021/acsami.3c10418
• Publication Date: 2023-09-29T13:49:40Z
• Authors: Veera Prabu Kannan; Vinothkumar Lourd...; Immanuel Paulraj; Chia-Jyi Liu; Sridharan Madanag...
• Keywords: Spark Plasma Sintering; Hot pressing

Mg3Sb2-based Zintl compounds have garnered recent attention as promising materials for thermoelectric applications due to their low thermal conductivity and high zT values n-type materials. However, the of p-type are lower compared counterparts. Through a straightforward process involving cold pressing evacuating-and-encapsulating sintering, we successfully synthesized variety Mg3–xZnxSb2/Sb composites by adding ZnSb-4%Sb composite into Mg3Sb2 host material. Structural analyses provided insights role composite, demonstrating its significance in Zn doping on Mg sites Sb acting an additive composite. The introduction tetrahedral enhances concentration carriers, while presence highly conductive grains facilitates movement charge carriers between adjacent Mg3–xZnxSb2 grains, thereby promoting mobility. Consequently, electrical resistivity decreases content increases. At 710 K, Mg1.91Zn1.09Sb2/Sb exhibits lowest resistivity, measuring 5.1 mΩ-cm, which is 46 times than that host. Furthermore, value increases with higher (x), benefiting from combination improved power factor reduced conductivity. Significantly, our fabrication enables us achieve maximum 0.58 at K This achievement can primarily be attributed 8-fold enhancement