Organic-Inorganic Hybrid Perovskites

Abstract

The dielectric functions and optical constants of various organic-inorganic hybrid perovskite semiconductors, including HC(NH₂)₂PbI₃, CH₃NH₃PbI₃, CH₃NH₃PbBr₃ and CH₃NH₃PbCl₃, are summarized. For CH₃NH₃Pb(I, Br)₃ alloys, the variation of the dielectric function with Br content, calculated by applying the energy shift model, is presented. This chapter also provides the optical constants of perovskite secondary phases, such as semitransparent δ-phase HC(NH₂)₂PbI₃, PbI₂ and CH₃NH₃I. It has been established that the dielectric functions of all the hybrid perovskite compounds can be parameterized by assuming several transition peaks calculated from the Tauc-Lorentz model. In particular, by incorporating Tauc-Lorentz peaks with very small amplitudes, the absorption coefficient spectra of the hybrid perovskites are reproduced almost perfectly in a quite wide range of α = 10²–10⁶ cm⁻¹. In this chapter, the Tauc-Lorentz parameters obtained from the above parameterization scheme are summarized, together with the tabulated optical constants.