Study of Novel Double Perovskites La2BB′O6 (B = V, Cr & Sc and B′ = Sc, Co & Ni) for Solar Cell Applications: A DFT study

Abstract

Here we investigated the electronic, magnetic and optical properties of Novel Double Perovskites La₂BB′O₆ (B = V, Cr & Sc and B′= Sc, Co & Ni) using ab-initio density function theory (DFT) calculations. The GGA and GGA(+U) (Hybrid term) band structures for La₂CrCoO₆, La₂CrNiO₆, La₂ScNiO₆, La₂VNiO₆ and La₂VScO₆ reveal metallic behavior in spin-up state, whereas, the minority spin channel have a band gap around the Fermi level (E_F) recommend semiconducting behavior, confirm half metallicity. The GGA and GGA+U band gaps for La₂CrCoO₆, La₂CrNiO₆, La₂ScNiO₆, La₂VNiO₆ and La₂VScO₆ are 0.95eV, 1.15eV, 1.63eV, 1.22eV & 3.54eV and 1.67eV, 1.22eV, 3.95eV, 2.0eV & 3.57eV respectively. The magnetic moments (µB) reveals that these materials are half-metallic ferromagnetic and transition metals Cr, V, Sc, Co and Ni contribute maximum to total spin magnetic moments (µB), whereas, La contributes minimum to (µB). La₂CrNiO₆ (LCNO) has the maximum total spin magnetic moment, 4.0µB, while the total spin magnetic moment of La₂ScNiO₆ (LSNO) is minimum, 0.9µB. Optical conductivity , for these NDPs materials are found in the range of 14,927 at 20.99eV to 11,205 at 21.55eV. The absorption coefficient calculated for La₂CrCoO₆ has maximum value of 401.082 at 21.973eV. The optical reflectivity for the material La₂CrNiO₆ has the maximum value of 0.696 at 0.04eV, whereas the NDP material La₂VScO₆ has the lowest value of 0.369 at 0.013eV via both schemes. Our investigations confirmed that these materials have high potential in ferromagnetic, spintronic, microelectronic and optoelectronic technologies. These materials can be used for solar cell applications.