Figure of merit analysis of nanostructured thermoelectric materials at room temperature

Abstract

In this paper, we mainly focused on analyzing the thermoelectric property i.e. figure of merit of different nanostructured materials in room temperature (300–310 K). Here we studied the transition-metal dichalcogenides, particularly Molybdenum Disulfide (MoS2); Metal Oxides, specifically Zinc Oxide (ZnO); and conventional semiconductor materials, i.e. n-type and p-type Silicon (Si) and Silicon Germanium (SiGe). At first, we calculated the electrical conductance (Ge), by using electronic density functional theory (DFT). Similarly, we calculated the thermal conductance (κ) using Tersoff empirical potential (TEP) model. With these calculated values of Ge and κ and the Seebeck coefficient (S), we calculated the figure of merit (ZT) at different room temperatures. The main findings of our research were the increased ZT of MoS2, which is slightly larger than p-type Si while, 2∼3 times larger than ZnO and 100∼103 times larger than conventionally used SiGe and n-type Si at room temperatures. We have further investigated a thermoelectric generator (TEG) device with these materials to validate our result.