Reducing lead toxicity in the methylammonium lead halide MAPbI(3): Why Sn substitution should be preferred to Pb vacancy for optimum solar cell efficiency

Article

关键词: PEROVSKITE THIN-FILMS;    NATIVE DEFECTS;    LIGHT;    PERFORMANCE;    TRANSITIONS;    FORMABILITY;    STABILITY;    DIFFUSION;    ENERGY;    LAYERS;   

DOI  :  10.1103/PhysRevB.101.054108

来源: SCIE

【 摘 要 】

Methylammonium lead halide (MAPbI(3)) perovskite has emerged as one of the frontier optoelectronic semiconductors. To avoid lead toxicity, the role of Sn substitution and Pb vacancy (Pb-boxed times) are addressed in regulating stability and solar cell efficiency of MAPb(1-X-Y)Sn(X) boxed times(Y) I-3 perovskite using hybrid density functional theory (DFT). The role of spin-orbit coupling (SOC) and the electron's self-interaction error are examined carefully. We find to reduce the Pb content from pristine MAPbI(3), Sn substitution has a more favorable thermodynamic stability than creating Pb-boxed times. Moreover, on substituting Sn, due to strong s-p and p-p couplings, the lower parts of the conduction band gets shifted downwards, which results in the reduction of the band gap (direct). This further helps us to get a high optical absorption coefficient (redshifted) and maximum solar cell efficiency in MAPb(1-X)Sn(X)I(3) for 0 < X <= 0.5.

【 授权许可】

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