First-principles study of structural, electronic, mechanical, optical, thermodynamic and thermoelectric properties of ternary ZnSnN2 and ZnMoN2 nitrides

Abstract

This paper mainly reports structural, electronic, mechanical, optical, thermodynamic and thermoelectric properties of ternary ZnSnN2 and ZnMoN2 nitrides. Calculations are carried-out (using Wien2k software) to examine the properties of ZnSnN2 and ZnMoN2 nitrides. Both nitrides have negative formation energies confirming their structural and thermodynamic stability. Electronic band structure and DOS plots show semiconducting nature of ZnSnN2 (with a direct band gap = 0.23 eV), while semi-metallic behavior of ZnMoN2. Mechanical properties indicate the brittle behavior of both (ZnSnN2 and ZnMoN2) nitrides. Calculated mechanical properties show anisotropic behavior of ZnSnN2 and ZnMoN2 nitrides. Both nitrides show an average reflectivity of about 20–35% (in the visible region) which show their suitability to enhance light absorption in solar panels and also their use for anti-reflective coatings in optical devices. For ZnSnN2 and ZnMoN2 nitrides, thermodynamic properties are also calculated at different pressures (0–100 GPa) and at different temperatures (0–2000 K). Thermoelectric properties are calculated using Boltztrap2 code. High figure-of-merit (ZT = 2.38 of ZnSnN2 at room temperature) reflects its suitability to use in thermoelectric systems. Combination of electronic optical and thermoelectric properties indicate that the ZnSnN2 and ZnMoN2 nitrides have great potential for use in electronic, optical and thermoelectric devices.