High efficient perovskite solar cell material CH3NH3PbI3: Synthesis of films and their characterization.

Hybrid organometal perovskites have been emerged as promising solar cell material and have exhibited solar cell efficiency more than 20%. Thin films of Methylammonium lead iodide CH₃NH₃PbI₃ perovskite materials have been synthesized by two different (one step and two steps) methods and their morphological properties have been studied by scanning electron microscopy and optical microscope imaging. The morphology of the perovskite layer is one of the most important parameters which affect solar cell efficiency. The morphology of the films revealed that two steps method provides better surface coverage than the one step method. However, the grain sizes were smaller in case of two steps method. The films prepared by two steps methods on different substrates revealed that the grain size also depend on the substrate where an increase of the grain size was found from glass substrate to FTO with TiO₂ blocking layer to FTO without any change in the surface coverage area. Present study reveals that an improved quality of films can be obtained by two steps method by an optimization of synthesis processes. [ABSTRACT FROM AUTHOR]