Excellent optical and thermoelectric features of two-dimensional half-metallic ferromagnet Zn1-x(TM)xO: A first principle investigation

The electronic, magneto-optical, and thermoelectric properties of graphene-like ZnO nanosheets doped with transition-metal TM (= Fe, Co, Ni, or Cu) were analyzed using spin-polarized first-principles computations. When a TM atom substitution with the Zn atom, the resultant material exhibits significant spin-polarization around the Fermi level and displays a half-metallic ferromagnet within the PBEsol-GGA. Doped ZnO nanosheets by Fe-, Co-, Ni-, and Cu-dopants generate the total magnetic moment of 4 & mu;B, 3 & mu;B, 2 & mu;B, and 1 & mu;B, respectively, which is produced primarily by the TM-3d atoms. The p-d hybridization explains the ferromagnetic interactions caused by the robust coupling among Co-, Ni-, or Cu-3d and anion O-2p orbitals. We have investigated the optical characteristics of TM-doped ZnO nanosheets in parallel (E ǁX) and perpendicular (E ǁZ) polarization directions. Our analysis demonstrates that the Zn1-x(TM)xO two-dimensional nanosheets can absorb visible sunlight in the (E ǁX) polarization direction comparatively to pristine ZnONS. Along the x-axis, we studied the Seebeck coefficient, electrical, electronic thermal conductivities, and power factor for various temperatures. All the TM-doped ZnO (2D) nanosheets demonstrate superior electrical conductivity and high power factor in n-type doping than in ptype doping. According to these findings, TM-doped ZnO nanosheets could represent the next evolution in Spintronic, photovoltaic cells, and thermoelectric technologies.