Mixed Sulfur and Iodide-Based Lead-Free Perovskite Solar Cells.

The use of divalent chalcogenides and monovalent halides as anions in a perovskite structure allows the introduction of 3+ and 4+ charged cations in the place of the 2+ metal cations. Herein we report for the first time on the fabrication of solar cells exploiting methylammonium antimony sulfur diiodide (MASbSI2) perovskite structures, as light harvesters. The MASbSI2 was prepared by annealing under mild temperature conditions, via a sequential reaction between antimony trisulfide (Sb2S3), which is deposited by the chemical bath deposition (CBD) method, antimony triiodide (SbI3), and methylammonium iodide (MAI) onto a mesoporous TiO2 electrode, and then annealed at 150 °C in an argon atmosphere. The solar cells fabricated using MASbSI2 exhibited power conversion efficiencies (PCE) of 3.08%, under the standard illumination conditions of 100 mW/cm2.