Thermoelectric materials are crucial in renewable energy conversion technologies to solve the global energy crisis. The thermoelectric performance of devices depends primarily on the type of materials used and their properties, including Seebeck coefficient(S), electrical conductivity (σ), thermal conductivity (κ), and thermal stability. Approaches such as nanostructuring, nanocomposites, and doping are found to enhance thermoelectric responses by simultaneously tuning various properties within a material. 2D materials have advantages over bulk(3D) materials due to their quantum confinement effect, energy filtering effect and phonon engineering. Newly investigated materials such as graphene, transition metal dichalcogenides, black phosphorus, etc., are attractive for unique thermoelectric properties. Among the different classes of 2D material, TMDCs are showing better thermoelectric performance due to their ultra-low κ and high S, which enhance the thermoelectric figure merit (zT). Compared with other 2D TMDCs, MoSe2 and SnSe2 show better thermoelectric properties (high power factor and ultra-low κ) at room temperature, which can be very interesting for room temperature thermoelectric devices. For the case of monolayer and bilayer, MoSe2 shows thermal conductivity of 35 W/m.K and 21W/m.K [1], respectively. We are proposing twist angle-dependent thermal properties of bilayer MoSe2 as well as TMD based superstructures with different stacking orders.
Reference:
Xian Zhang et al., “Measurement of Lateral and Interfacial Thermal Conductivity of Single- and Bilayer MoS2 and MoSe2 Using Refined Optothermal Raman Technique”. ACS Appl. Mater. Interfaces, 2015, 7, 25923−25929.