Electronic, optical and thermoelectric properties of CaO:F mono-layer: a DFT study

Abstract

Abstract Based on density functional theory, structural, electronic, optical and thermoelectric properties of CaO and CaO:F mono-layer compounds have been investigated. Both structures have elastic stability, with Young’s and Shear’s moduli of 57.78 (N/m) and 23.85 (N/m), respectively, which shows the resistance of these compounds against stress and strain. The reduction of Poisson’s ratio with the introduction of F atom indicates the tendency to ionic bonds between atoms, and its magnetic moment reaches to 0.84 μ B. The CaO compound is a p-type semiconductor with 2.6 eV, and by adding a F atom to it, it has become a half-metal. In the CaO:F mono-layer, we see a red shift in the real- and imaginary-dielectric function compared to the CaO one. At a temperature of 50 K, the Seebeck coefficient is 32 (μVK−1) and at room temperature it reaches 24 (μVK−1), also the figure of merit coefficient at these temperatures is 1.2 and 0.8, which indicates its thermoelectric capability.