Ab Initio Study of Thermoelectric Transport Properties of Zintl Phase Nitride Ca2ZnN2

The growing demand for alternative energy solutions has driven interest in thermoelectric materials for waste heat recovery. Zintl phases are promising thermoelectric candidates, yet the transport properties of Ca 2 ZnN 2 remain largely unexplored. In this work, we combine density functional theory and semiclassical Boltzmann transport calculations to predict the intrinsic thermoelectric properties of Ca 2 ZnN 2 . The compound crystallizes in a tetragonal structure and exhibits intrinsic p‐type behavior, with high electrical conductivity ( σ = 1.63 × 10 4 S cm) −1 and hole mobility of ( μ h ≈ 10 cm 2 V −1 s) −1 at 300 K. Polaroptical phonon scattering dominates carrier relaxation, yielding lifetimes around 10 −15 s. The lattice thermal conductivity is relatively large ( k L = 14.0 W m −1 K −1 for p‐type and 13.0 W m −1 K −1 for n‐type), resulting in modest room‐temperature figures of merit: ZT = 0.017 (p‐type) and ZT = 0.018 (n‐type). However, ZT increases with temperature and carrier concentration, reaching 0.07 (p‐type) and 0.08 (n‐type) at 500 K for n = 1 × 10 20 cm −3 . Notably, p‐type doping benefits from higher mobility and power factor despite n‐type having larger Seebeck coefficients, making Ca 2 ZnN 2 a promising candidate for p‐type thermoelectric applications.