DFT study of structural optoelectronic and thermoelectric properties of CuNiO ferromagnetic alloys

Abstract In this study, the structural, electronic, and thermoelectric properties of pure NiO and Cu-doped NiO were investigated. The structural and optoelectronic properties of nickel oxide and in the supercell containing 32 atoms CuNi 15 O 16 were obtained by density functional theory (DFT) using the generalized gradient approximation (GGA) with the Hubbard correction potential U. The theoretical results obtained using the quantum espresso code show that the ferromagnetic character of the supercell structure is more stable than the antiferromagnetic configuration, and incorporating copper in the NiO matrix reduces the spin-up band structure. The value of the band gap channel is approximately 1.7 eV. The spin-down states cross the Fermi level and indicate the half-metal character of the CuNiO alloys. These results suggest that Cu-doped NiO is a potential candidate for infrared light and spintronic applications. The transport coefficients of the nickel oxide and copper doped NiO were calculated using the semi-classical Boltzmann theory implemented in BoltzTraP code. The thermoelectric properties, such as the Seebeck coefficient, power factor, and figure of merit, are calculated with respect to the chemical potential and carrier concentration in the temperature range of 300 K–800 K. We found an increase in the factor of merit and switching of NiO oxide from n-type to p-type after copper incorporation.