Synthesis and characterization of CH3NH3PbI3 perovskite thin films obtained in one step

Abstract Organic-inorganic hybrid perovskites have been studied in recent years because of their potential application in the fabrication of high efficiency solar cells. One of the disadvantages of these compounds is the chemical instability to environmental conditions. In the present work, thin films of CH3NH3PbI3 were obtained from a single-step deposition of a 1 M solution of the precursors in N–N dimethylformamide; the substrate was chemically treated glass. Tetragonal symmetry was determined by X-ray diffraction, this technique allowed us to monitoring the stability of the compound. Thin films were also characterized by scanning electron microscopy, showing a morphology based on needles formed of grains with approximately 150 nm, which are covering about 90% of the substrate surface. Finally, by means of absorbance measurements in the UV–Vis region, a direct gap of 1.54 eV was obtained. This value is considered ideal for hybrid perovskites.