A‐Site Cation Replacement of Hydrazinium Lead Iodide Perovskites by Borane Ammonium Ions: A DFT Calculation

Organometallic perovskites have become one of the most common multifunctional materials in optoelectronic research fields. This research studies density functional theory calculation on orthorhombic hydrazinium lead iodide (N₂ H₅ PbI₃ ) perovskite by replacing A-site cation with a borane ammonium (BH₂ NH₃ ⁺ ) ion. The perovskite showed a significant structural deformation and an orthorhombic to triclinic phase transition due to A-site ion replacement. The N₂ H₅ PbI₃ perovskite has a band gap of 1.64 eV, suitable for the solar cell absorber layer. The band gap has increased to 2.12 eV after complete A-site ion replacement. All structures showed a high absorption coefficient over 10⁴ cm^-1 in the low wavelength region and an increase in refractive index from 2.5 to 2.75 due to ion replacement. All the structures showed high optical conductivity of 10¹⁵ s^-1 order in the blue wavelength region. These new perovskite structures hold the potential to provide a revolution in optoelectronic research.