Deciphering the Effect of Synthesis Methods on the Thermoelectric Properties of ZnO Nanostructures

Nanoparticles (NPs) have attracted significant research interest due to their exceptional properties and wide-ranging applications across diverse industries. Among these nanoparticles, zinc oxide nanoparticles (ZnO NPs) have emerged as ubiquitous and extensively utilized nanomaterials in contemporary industrial settings. ZnO exhibits characteristics as an n-type semiconductor, featuring a wurtzite crystal structure and a wide band gap, alongside exceptional optical, electronic, and photonic properties. Its remarkable chemical stability and high electrical conductivity further enhance its appeal as a candidate for thermoelectric (TE) materials. In this thematic review, we comprehensively explore the influence of various synthesis techniques on the formation of ZnO nanostructures and their impact on thermoelectric properties. These techniques encompass sputtering, sol-gel, hydrothermal, co-precipitation, solvothermal, and processes involving plant extracts. Additionally, we delve into the consequential impact of these techniques on the thermoelectric performance of ZnO. Within this thematic review article, we present an in-depth analysis of the distinct thermoelectric characteristics exhibited by ZnO when doped with various metals such as Al, Ga, Dy, and Ni, as well as in its undoped state.