Theoretical insights into the thermoelectric performance of 2D MXene Ti3C2

A class of two-dimensional (2D) materials known as MXenes has a layered structure and is expected to exhibit unique thermoelectric (TE) properties. Despite the high expectations for certain MXenes’ TE capabilities, there has been surprisingly limited theoretical research into this area. Inspired by the recent successful growth of 2D monolayer Ti3C2 MXene, here we explore the potential of pristine monolayer Ti3C2 as a TE material by means of first-principles density functional theory calculations in conjunction with a semi-classical Boltzmann transport approach. Furthermore, we investigate several crucial thermal and electrical transport parameters within the constant relaxation time approximation, including electron thermal and electrical conductivities. In addition, we calculate the Seebeck coefficients, power factor, and figure of merit in the Ti3C2 MXene monolayer and provide a conclusion of their suitability as a TE material. The electronic thermal conductivity, expressed in terms of the reduced chemical potential, increases with rising absolute temperature. In contrast, the electrical conductivity shows minimal changes with the temperatures under consideration. Our computational results set a reference for benchmarking and validation for experimentalists, enabling them to compare the TE performance of other semiconducting and functionalized MXenes.