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Title: Doping and Anisotropy–Dependent Electronic Transport in Chalcogenide Perovskite CaZrSe 3 for High Thermoelectric Efficiency

The potential of an environmentally friendly and emerging chalcogenide perovskite CaZrSe3for thermoelectric applications is examined. The orthorhombic phase of CaZrSe3has an optimum band gap (1.35–1.40 eV) for single‐junction photovoltaic applications. The predictions reveal that CaZrSe3possesses an absorption coefficient of ≈4 × 105cm−1at photon energies of 2.5 eV with an early onset of optical absorption (≈0.2 eV) well below the optimum band gap. Seebeck coefficient,S, is inversely proportional to the carrier mobility as the calculated average effective mass for electrons is higher than for holes;p‐type doping enhances the electrical conductivity, σ. The electronic thermal conductivityκeremains low at all temperatures. The upper limit of the thermoelectric figure of merit (ZTe) attains ≈1.0 when doped at specific chemical potentials, while a high Seebeck coefficient contributes to the ZTe = 1.95 at 50 K forp‐type doping with 1018cm−3carrier concentration, demonstrating high thermoelectric efficiency.

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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Theory and Simulations
Medium: X
Sponsoring Org:
National Science Foundation
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