Structural and Photoelectric Properties of CsPbI3 Perovskite Solar Elements Made with Added Hydroiodic Acid

Cesium lead triiodide (CsPbI 3 )-based inorganic perovskites are the most promising material for the manufacture of perovskite solar cells (PSC) due to their optimal band gap width of about 1.72 eV and high light absorption coefficient, which is characteristic for the cubic structure of CsPbI 3 known as the black phase. The formation of such a structure at relatively low temperatures requires the addition of hydroiodic acid (HI) to the perovskite solution, from which the material is prepared. Structural, morphological, optical, and photoelectrical parameters of CsPbI 3 were studied. The most important characteristics of CsPbI 3 -based PSC with maximum efficiency of 8.85% obtained when the HI acid concentration was 66 μL/mL are described.