Microstructural modification of organic-inorganic lead iodide Perovskite thin film by Anti-solvent treatment

Methylammonium lead iodide perovskite (CH3NH3PbI3) has been recently used as high-performance and low-cost light absorber in third generation solar cells. Perovskite thin‐film can be prepared by either single-step procedure or sequential two-step deposition technique. Traditional two‐step spin coating method is suffered from high roughness and uncovered pin-hole areas. In this study, simple one-step deposition method was investigated for fabricating smooth and pin-hole free perovskite thin film by anti-solvent treatment method. In this method, perovskite phase nucleation and growth was accelerated by dropping anti-solvents on dimethylformamide based precursor solution during spin coating, which leads to perovskite thin film with small and uniform grains. The effects of the anti-solvent, amount of anti-solvent and delay time for anti-solvent dropping were investigated. Eventually, it was shown that the anti-solvent technique is an effective method to fabricate uniform perovskite layer. That perovskite layer formed with this anti-solvent treatment method can be used to fabricate highly efficient perovskite solar cells.

Keywords:

Methylammonium lead iodide perovskite , Anti-solvent treatment , Thin film