Thermoelectric Properties of Doped-Cu₃SbSe₄ Compounds: A First-Principles Insight

Abstract

This work reports the first systematic study of the effects of substitutional doping on the transport properties and electronic structure of CuSbSe. To this end, the electronic structures and thermoelectric parameters of CuSbSe and CuSbM Se (M = Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Bi) were systematically investigated by using density functional theory and the Boltzmann semiclassical transport theory. Substitutional doping at Sb site with IIIA (M = Al, Ga, In, Tl) and IVA (M = Si, Ge, Sn, Pb) elements considerably increases the hole carrier concentration and consequently the electrical conductivity, while doping with M = Bi would be adequate to provide high S values. Changes in calculated thermoelectric parameters are explained based on the effects of the dopant element on the electronic band structure near the Fermi level. We also present an extensive comparison between thermoelectric parameters here calculated and available experimental data. Our results allow us to infer significant insights into the search for new materials with improved thermoelectric performance by modifying the electronic structure through substitutional doping.

Regulation of the Crystal Structure Leading to the Bandgap Widening and Phonon Scattering Increasing in Cu3SnS4‐Cu3SbSe3 Chalcogenides

“…The bond SbSe might be more stronger than CuSe, as its bond energy (0.53 eV) is higher than that of CuSe (0.16 eV) in Cu 3 SbSe 4 . The newly created network CuSe is of great significance to act as hole conduction paths . It is noted upon Sb and Se incorporation the bond lengths of four bonds (CuS, CuSe, SnS, SbSe) alter nearby the Sb and Se sites parallel to the b‐c crystal plane, represented by the slight increase of bond lengths SnS (2.476–2.50 Å), CuSe (2.428–2.450 Å) and SbSe (2.624–2.640 Å).…”

“…[25] The newly created network CuSe is of great significance to act as hole conduction paths. [22,26] It is noted upon Sb and Se incorporation the bond lengths of four bonds (CuS, CuSe, SnS, SbSe) alter nearby the Sb and Se sites parallel to the b-c crystal plane, represented by the slight increase of bond lengths SnS (2.476-2.50 Å), CuSe (2.428-2.450 Å) and SbSe (2.624-2.640 Å). However, the bond length of CuS (2.30-2.28 Å) tend to decrease, see Figure 2a.…”

Thermoradiative Cells Based on a p-type Cu3SbSe4 Semiconductor: Application of a Detailed Balance Model

“…14 > 17 > 19 - 26 As matter of fact, we have recently published a systematic theoretical work on the electronic structure and thermoelectric properties of doped-Cu 3 SbSe 4 semiconductors by using density functional theory (DFT) calculations and semiclassical Boltzmann theory. 27 In this paper, we propose a detailed analysis of TRCs based on p-type Cu3SbSe4 semiconductor (Cu3SbSe4 TRC). Concretely, an accurate description of the electronic structure of Cu 3 SbSe 4 is obtained through DFT calculations.…”

“…As said, we have recently reported a systematic study the effects of substitutional doping on the electronic structure of Cu 3 SbSe 4 . 27 Therefore, only the main features are here discussed. As seen in Fig.…”

“…Note that the Cu 3 SbSe 4 figure of merit is quite much large what could lead to obtain much larger current from TRCs using setups similar to that used by Ono et al;(4) The electronic structure and thermoelectric properties of the material can be tuned through the chemical doping. 27 Thus, larger ZT values could lead to an improvement of properties involved in thermoradiative conversion, such as rate of recombination, diffusion lengths and change of resistivity with temperature. Under this scope, the consideration of Cu3SbSe4, a material that can change its electronic properties (not only the bandgap) somehow in an easy way upon chemical doping, is of paramount importance to start the path of finding alternative candidates to build highefficiency TRCs.…”