Abstract
Thermoelectric materials can convert waste heat energy into electrical energy based on Seebeck and Peltier effects. Converting waste heat into electricity through the thermoelectric power of solids without producing greenhouse gas emissions could be an important part of the solution to today’s energy challenges. Furthermore, the development of novel thermoelectric materials with high properties is a means of controlling global warming and environmental pollutants. The development of high-efficiency thermoelectric materials is one of the important research directions for solar power utilisation. This theoretical study focuses on traditional thermoelectric materials and different aspects of their design and development. Theoretically, we predict their electronic and optical properties and simulate charge transfer between the interfaces using density functional theory (DFT), the generalised gradient approximation of Perdew–Burke–Ernzerhof exchange-correlation functional. The thermal transport and electronic properties are compared using the Boltzmann transport theory and Mott derived equations.
Traditional thermoelectric “Skutterudite phases, half-Heusler intermetallic compounds, metal chalcogenides, composite metal carbides, rare-earth metal pnictogenides and organometallic materials with the clathrate structure” and 2D-materials are used to generate 2D Hetero-thermoelectric superlattice materials. However, the electronic results obtained revealed a reduction in the calculated bandgap and an increase in the slope of the density of state at the Fermi level and the energy bands of the generated 2D Hetero-thermoelectric structures. Partial density of states showed that various orbitals were present in the traditional thermoelectric/2D Hetero-thermoelectric materials and their contributions at the Fermi level. The dielectric function was found to decrease in 2D Hetero-thermoelectric layers generated. Further, spin-polarized first-principle studies were used to determine contributions from the spin–down and
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spin–up eigenstates. It was evident that the superlattice structures had an improved performance compared to the traditional thermoelectric materials. The 2D Hetero-thermoelectric materials also improved electronic, optical and charge generation/separation and yielded a better thermoelectric material. Therefore, it is anticipated that the concluded theoretical studies could be useful for designing new generation-thermoelectric materials. The fully explored charge transfer mechanism, electronic and optical properties pave the way for their will resulting in energy conversion and environmental remediation.