Phase and Composition Tunable Out-of-Plane Seebeck Coefficients for MoS₂-Based Films

Abstract

Two-dimensional layered transition-metal dichalcogenides (TMDCs) are promising materials for thermoelectric applications due to their superior electronic and phonon transport properties due to a favorable large energy bandgap with an atomically thin layer, which also provides unique density of states for confined electrons and holes. Seebeck coefficient controllability in TMDC materials is essential. This paper demonstrates controllable out-of-plane Seebeck coefficients for large-area MoS 2 thin films by changing their phase and composition. We address large Seebeck coefficient differences at room temperature using large-area single-and mixed-phase MoS 2 thin films by adjusting the reaction temperature during sampling and also discuss interface thermal resistance in sandwiched Cu/MoS 2 /Cu structures. Our findings confirm an ideal platform to control thermoelectric properties for low-dimensional materials for small-scale energy harvesting and microcooling technologies.

Electrical conductivity, Seebeck coefficient, and crystal growth of p-type tellurium films through temperature dependent RF sputtering

“…c) compares the Seebeck coefficients of the Te films with those of bulk samples reported in previous studies[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Notably, most thin films and Te based films exhibited high Seebeck coefficients at high processing temperatures over the 200 °C.…”

A short account of thermoelectric film characterization techniques

“…T was generated between the ends of the films along the z-direction using the micro-Peltier as a heater; (g) Schematic illustration of the measurement system used for the S⊥ of the Cu/multilayer MoS2 (~7 nm-thick)/Cu structure; (h) Seebeck voltage measurement contacts during S⊥ measurement. [44] (i) Schematic of the hBN-encapsulated twisted-bilayer Gr device geometry and the contact pads used for the cross-plane TE measurement. [45] A 3ω method utilizing microfabrication techniques has been devised for the concurrent determination of the S⊥ and f,⊥ in an n-type Si(75 Å)/Ge(15 Å) quantum-dot SL.…”

“…The S⊥ of CVD-grown MoS2 (2D layered metal dichalcogenides (TMDCs)) film has been measured using a steady state method in order to steady the variation of S⊥ in mixed-phase MoS2 thin films. [44] Using conventional poly(methyl methacrylate) (PMMA)-assisted wet chemical etching, MoS2 thin films were deposited onto a Cu/SiO2/Si substrate. [55] Finally, RF sputtering was used to form a Cu thin layer (200-nm thick) on the MoS2/Cu/SiO2/Si substrate (i.e.…”

Quantitative measurement of figure of merit for transverse thermoelectric conversion in Fe/Pt metallic multilayers

“…Several recent reports have proposed a measurement method for the out-of-plane Seebeck coefficient, but this method does not account for the influence of contact/interfacial thermal resistances when measuring the temperature difference between the top and bottom surfaces of the thin-film sample [39,40]. In contrast to the SE, since the ANE allows the orthogonal configuration between the heat and charge currents, it is sufficient to evaluate ST and σyy in the in-plane direction and κxx in the out-of-plane direction.…”