Theoretical determination of superior high-temperature thermoelectricity in an n-type doped 2H-ZrI₂ monolayer

Abstract

Two-dimensional materials with competitive figure of merit zT are extremely desirable for fabrication of thermoelectric modules. In the present work, we systematically evaluate the thermoelectricity of monolayer 2H-ZrI2 through first-principles...

Ab Initio Discovery of Group IV–V Monolayers with Superlative Mechanical, Electronic, and Transport Properties

“…For inorganic semiconductors, the coherence length of thermally activated carriers at room temperature approaches the acoustic phonon wavelength and is much larger than their lattice constants. On the basis of the effective mass approximation, we can thus evaluate the carrier mobility of 2D systems by the DP theory from the following analytical expression ,,,, μ 2 normalD = 2 e normalℏ 3 C 2 normalD 3 k normalB T false| m * false| 2 E normalD normalP 2 where e is the elementary charge, ℏ is the reduced Planck constant, k B is the Boltzmann constant, and T is the absolute temperature that is set to be 300 K in all our calculations. C 2D , m *, and E DP refer to the elastic modulus, effective mass of carriers, and DP constant, respectively, along two orthogonal transport directions of a rectangular 3 × 1 × 1 supercell (as shown in Figure ), which are derived from C 2 normalD = ∂ 2 E α ′  M normalI normalV X normalV / ∂ η 2 S 0 , .25em m * = normalℏ …”

“…Recent studies have exposed that some of 2D α-M IV X V , α-M III X VI , and γ-M IV X VI compounds yield a quartic dispersion as well in their top valence bands, 30,36,42,82,83 which has a great consequence on temperature-independent thermopower and efficient thermoelectric performance. 84,85 Without loss of generality, the orbital-resolved DOS presented in Figure S8 indicates that in all semiconducting systems, the states in the vicinity of the Fermi level have contributions from the s and p orbitals of constituent atoms. The strong hybridization arising from the orbital overlap confirms the formation of covalent bonds, agreeing with the prior analysis of ELF projections and BO model.…”

“…97 For inorganic semiconductors, the coherence length of thermally activated carriers at room temperature approaches the acoustic phonon wavelength and is much larger than their lattice constants. On the basis of the effective mass approximation, we can thus evaluate the carrier mobility of 2D systems by the DP theory 98 from the following analytical expression 36,39,80,85,99…”

Monolayer TiSi 2 P 4 as a high-performance anode for Na-ion batteries

“…To further prove the feasibility of the TiSi 2 P 4 monolayer as a promising anode for SIBs, we calculate the carrier mobility by the deformation potential (DP) theory of 2D materials [65,69,70]…”

A van der Waals p–n heterostructure of GaSe/SnS2: a high thermoelectric figure of merit and strong anisotropy

“…Some of them are applied to yield superior thermoelectric behaviors. 14–16 In recent years, a new type of structure has emerged in the 2D material landscape, van der Waals type heterostructures (vdWHs), where one 2D material is vertically stacked on the other and the layers are bonded together by the weak vdW interaction. 17 It can not only integrate the benefits of its constituents but also expand the properties of individual materials through new interface morphology, which has already been widely used in many fields such as electronics, optoelectronics, spintronics and electrochemistry.…”