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Using density functional theory calculations, we analyze the optical absorption properties of lead (Pb)-free metal halide perovskites (AB²⁺X₃) and double perovskites (A₂B⁺B³⁺X₆) (A = Cs or monovalent organic ion, B²⁺ = non-Pb divalent metal, B⁺ = monovalent metal, B³⁺ = trivalent metal, X = halogen). We show that if B²⁺ is not Sn or Ge, Pb-free metal halide perovskites exhibit poor optical absorptions because of their indirect band gap nature. Among the nine possible types of Pb-free metal halide double perovskites, six have direct band gaps. Of these six types, four show inversion symmetry-induced parity-forbidden or weak transitions between band edges, making them not ideal for thin-film solar cell applications. Only one type of Pb-free double perovskite shows optical absorption and electronic properties suitable for solar cell applications, namely, those with B⁺ = In, Tl and B³⁺ = Sb, Bi. Our results provide …