Evaluation of thermoelectric CdSnAs2 with intrinsically low effective mass

Reducing Effective Mass for Advancing Thermoelectrics in Sb/Bi-Doped AgCrSe2 Compounds

“…However, the carrier mobility could be deteriorated by the increased band effective mass in accordance with the Bardeen–Shockley deformation potential theory, leading to the weighted mobility becoming inversely proportional to inertial effective mass m I * (in the case of the isotropic transporting band, m b * equals m I *). Therefore, it is highly desired to decrease the band effective mass m b * for enhancing the weighted mobility and, thus, the B factor, − which has been widely used to optimize the zT value in half-Heusler ,− and chalcogenides. ,− According to the molecular orbital theory, orbital overlap in a solid results in broad bands, which are composed of the bonding and antibonding orbitals . It is found that compounds with small electronegativity differences usually result in a broader band dispersion, owing to stronger overlap, i.e., a larger bandwidth, which is meant to be a narrow parabola with a low m * band …”

An algorithm of calculating transport parameters of thermoelectric materials using single Kane band model with Riemann integral methods

“…According to both of the slopes in dρ / dT and dS/dT change around 600 K reported in Ref. 24 . This indicates that the electronic structure of Cd 0.95 Zn 0.05 SnAs 2 around that temperature has turned to a different state from room temperature.…”

“…To further verify the SKBcal, we repeat the same procedure as above and make a comparison between calculated data obtained using SKBcal with one more set of data reported in Ref. 24 , and show the results in Table 2 . The value of the band gap, band degeneracy, and K is set to 0.39 eV, 1, and 1, respectively.…”

“… Ref. 24 Cd 0.95 Zn 0.05 SnAs 2 T (K) ρ (mΩ cm) S (μV/K) n H (10 18 cm −3 ) m 0 * ( m e ) κ l (W/mK) 300 0.7810 − 47.75 2.260 0.03954 5.179 0.03877 (1.95%) 5.235 (1.08%) 400 0.8208 − 71.77 2.252 0.04514 3.648 0.04488 (0.576%) 3.697 (1.34%) 500 0.8615 − 86.59 2.240 0.04717 2.689 0.04480 (5.02%) 2.757 (2.53%) 600 0.8995 − 103.8 2.252 0.04943 2.089 0.04728 (4.35%) 2.312 (10.7%) 700 0.9014 − 108.6 2.417 0.04771 1.609 0.04560 (4.42%) 1.861 (15.7%) …”

Recent advances in designing thermoelectric materials

“…Several experimental studies also verified this approach with improved ZT values. [325][326][327][328] Crystal symmetry is largely determined by atomic ordering in a system. Therefore, altering atomic arrangements also can influence the transport properties.…”