First-principles calculations to investigate electronic, magnetic, and optical properties at (110) and (111) surfaces of Ni adsorption on CdO

Abstract

In this study, we utilised the GGA+U method via the WIEN2k software to investigate the structural, magnetic, and optoelectronic responses of two distinct surfaces, (111) and (110), to Ni adsorption on CdO at the Cd site. The analysis revealed that Ni/CdO (111) demonstrates properties akin to a semimetal or a zero-gap semiconductor across both spin orientations, while Ni/CdO (110) exhibits a metallic nature under similar conditions. These phenomena are predominantly ascribed to the orbital contributions from Ni-d, Cd-d, and O-p for the Ni/CdO (111), and Ni-d, Cd-d, and O-s for the Ni/CdO (110), respectively. A notable blue shift in the optical absorption spectra was observed for both materials. Utilising the Dielectric function, we calculated the dispersion of energy bands along with essential optical properties, including the absorption coefficient, energy loss function, and reflectivity, refractive index, and extinction coefficient. Magnetisation values for Ni/CdO (110) and Ni/CdO (111) were recorded at (−0.11794) µB and (2.17926) µB, respectively, influenced by the absorption spectrum's blue shift. Additionally, transport properties were evaluated using the BoltzTraP software over a temperature range of 0 to 800 K. Our findings suggest that Ni/CdO (110) and Ni/CdO (111) are significant for applications in spintronics and energy devices.