Optical and thermoelectric response of RhTiSb half-Heusler

Abstract

Structural, electronic, optical and thermoelectric response of the cubic RhTiSb compound is reported using TB-mBJ potential. The calculated results for the band structure and DOS confirm that the RhTiSb is a nonmagnetic (NM) semiconductor with an indirect bandgap of 0.71 eV. The main optical parameters such as dielectric function, absorption coefficient, refractive index and optical reflectivity were estimated for emission upto 14 eV. The RhTiSb half-Heusler exhibits a maximum absorption in the visible and ultraviolet region. By using the Boltzmann transport equations as incorporated in BoltzTraP code, the thermoelectric characteristics were calculated. The main properties which describe the aptitude of material in thermoelectric environment such as Seebeck coefficient and figure of merit were calculated. The high values of figure-of-merit (ZT [Formula: see text] 0.7) were observed in large range of temperature indicating that RhTiSb have a good thermoelectric performance.

Rhodium-based half-Heusler alloys as thermoelectric materials

“…The observed value of α is comparable with reported work for RhTiP and RhTiSb at a particular temperature range. 46,47…”

“…We noticed very few theoretical works on rhodium-based hH alloys. [46][47][48] However, there are no reports on the dynamical stability and k of these systems, which is very important in calculating ZT values and other features of the systems. Therefore, extensive investigation is necessary to understand the TE properties.…”

Rhodium based half-Heusler alloys as possible optoelectronic and thermoelectric materials

“…The values are comparable with the earlier works. [46][47][48] The band gap variation is small between the valence band maximum (VBM) and conduction band minimum (CBM). To note is, the band next to CBM moves close to it when P is replaced by As, Sb, or Bi (see Figure 5).…”

“…[43][44][45] From our literature survey, we noticed very few theoretical works on rhodium based hH alloys. [46][47][48] The reported work is preliminary and needs extensive investigation to understand the electronic, optical, mechanical, and thermoelectric properties of these materials. With this motivation, we explore RhTiZ (where Z are P, As, Sb, and Bi) which consists of two transition elements -Rh and Ti.…”

First-principles calculations to investigate mechanical, optoelectronic and thermoelectric properties of half-Heusler p-type semiconductor BaAgP

“…The HH materials with 18 valence electrons count (VEC) in the unit cell show thermoelectric properties. Many members of this family such as ScRhTe [6] TiCoSb [5], ScPtSb [7], TiNiSn [8], LiMgN [9], ScNiGa [10], PdZrGe [11], RhTiSb [12], RhFeX (X=Sn, Ge) [13], TaCoSn [14], HfNiSn [15],…”