Additive Effect of Formamidinium Chloride in Methylammonium Lead Halide Compound-Based Perovskite Solar Cells.

Perovskite compound-based solar cells using methylammonium lead iodine (CH₃NH₃I), lead iodine (PbI₂) and formamidinium chloride (HC(NH₂)₂Cl: FACl) were fabricated and characterized for improving the photovoltaic performance. Additive effects of FACl into the methylammonium-lead-halide perovskite layer on the photovoltaic properties were investigated. The slight additive of FACl into the perovskite layer promoted the crystal nucleation and growth with the monodispersed domain as the surface morphologies, which improved the photovoltaic performance with external quantum efficiency over ultra-violet–visible–near infrared region. The photovoltaic performance was improved by the surface morphology with the monodispersed crystal growth in the homogenous phase for promoting the photo-induced carrier-generation and extension of the carrier diffusion with suppression of the carrier recombination and trapping near pinholes, defects, voids, cracks and interface between the domains in the perovskite layer. [ABSTRACT FROM AUTHOR]