CuAlTe2: A promising bulk thermoelectric material

Abstract

Transport properties of Cu-based chalcopyrite materials are presented using the full potential linear augmented plane wave method and Boltzmann Semi-classical theory. All the studied compounds appear to be direct band gap semiconductors evaluated based on the Tran-Blaha modified Becke-Johnson potential. The heavy and light band combination found near the valence band maximum (VBM) drive these materials to possess good thermoelectric properties. Among the studied compounds, CuAlTe2 is found to be more promising, in comparison with CuGaTe2, which is reported to be an efficient thermoelectric material with appreciable figure of merit. Another interesting fact about CuAlTe2 is the comparable thermoelectric properties possessed by both n- type and p-type carriers, which might attract good device applications and are explained in detail using the electronic structure calculations.