The Electronic Structures And Optical Properties Of BaTiO₃ Doped With B/C/N Or Pd From First-principles Calculations

Energy problem has become one of the most important problems to mankind.It is the most effective way to resolve the crisis by the efficient use of solar energy,such as solar cells.The perovskite ferroelectric material,BaTiO₃,which can effectively inhibit the recombination of photogenerated electron-hole pairs due to its spontaneous polarization properties has developed rapidly in recent years.It has become one of the optimal materials for solar cells with low preparation costs at present.However,BaTiO₃ has a wide band gap which is not conducive to the absorption of visible light.Therefore,we need to regulate the size of the band gap.The electronic structures and optical properties of BaTiO₃ supercell doped with B/C/N and Pd are calculated by the first-principles calculations in this paper.There are two parts in this paper:For the first part,we construct a 2×2×2 Ba TiO₃ supercell and replace one oxygen atom by B,C or N atom.The results show that all these three kinds of single doping lattices greatly reduce the optical band gap and it is conducive to the absorption of visible light.Our absorption spectrum calculations confirm that both B and C-doped BaTiO₃ have a favorable performance in the absorption of visible light.However,N-doped BaTiO₃ doesn't present much improvement.For the second part,we take a 3×3×3BaTiO₃ supercell with B,C or N atom replacing one O atom and Pd atom replacing one Ti atom for our calculations.The results show that both?C,Pd?and?N,Pd?co-doping lattices can increase the absorption capacity for visible light to a large extent,but?B,Pd?co-doping lattice does not.Therefore,we conclude that B or C single doping lattices and?C,Pd?or?N,Pd?co-doping lattices should have an excellent performance on the absorption of visible light which is hopeful to apply in the field of photovoltaic materials.