High n-type and p-type thermoelectric performance of two-dimensional SiTe at high temperature

Abstract

From a device perspective, achieving great merits for both n-and p-type thermoelectric systems is particularly desirable. By first-principles calculations, electronic, phonon, and thermoelectric transport properties of 2D SiTe with three different structural phases are investigated, which are quadruple layer (QL), black-phosphorene-like (a-SiTe) and blue-phosphorene-like (b-SiTe), respectively. Of these three structure phases, b-SiTe possesses the best thermoelectric properties. This is because the DOS peak near the valence band results in a high Seebeck coefficient, further leading to a high power factor. We also demonstrate that strong phonon scattering heavily influences the lattice thermal conductivity K l of b-SiTe. With the combination of high power factor and low K l , the ZT max value of b-SiTe reaches 0.95 at T ¼ 1300 K for both n-and p-type doped systems. Therefore, 2D b-SiTe is a promising candidate for future high-temperature solid-state thermoelectric generators with a balanced performance of the nand p-legs.

Anisotropic to Isotropic Transition in Monolayer Group-IV Tellurides

“…First, we considered the structural properties of group-IV telluride monolayers. Previous research has established that group-IV telluride monolayers are dynamically stable in principle with the NaCl or distorted NaCl atomic arrangement [44,45,65,66]. In this system, the crystal structure of XTe (X = Si, Ge, Sn) belongs to the Pmn2 1 space group with a relative displacement ∆d between the group-IV atom and the Te atom along the y direction, while two-dimensional PbTe forms in a different P4/nmm structure without relative displacement [44], i.e., as a cleaved monolayer with a cubic NaCl structure shown in Figure 1 1, which were in good agreement with previous theoretical reports [29,67,68].…”

Preparation of n-type polyaniline/hexagonal boron nitride composites with a large thermoelectric power factor

“…The high TE performance is observed at low and medium temperatures with the use of such devices. 6 However, the instability under ambient conditions and electron trapping problems are the main drawbacks of n-type semiconductors. 7,8 Due to the high cost, hardness, and difficult processing of traditional inorganic TE materials, the researchers focused on conductive polymers as a promising alternative.…”

2D Materials Based on Main Group Element Compounds: Phases, Synthesis, Characterization, and Applications

“…By combining the low thermal conductivity, 2D β‐SiTe showed its potential as a high‐temperature thermoelectric material with n‐ and p‐type doping. [ 225 ] With a Si:Te stoichiometric ratio of 2:3, trigonal structure (P1c) Si 2 Te 3 is a stable phase and is predicted to exhibit a high thermoelectric performance at high temperatures (1000 K). [ 226 ] It can be prepared by the vapor transfer process or VLS process with a vapor Te source and Si supplied from either powder or a substrate.…”