Highly (100)-oriented CH3NH3PbI3(Cl) perovskite solar cells prepared with NH4Cl using an air blow method

The effects of adding NH₄Cl via an air blow process on CH₃NH₃PbI₃(Cl) perovskite solar cells were investigated. CH₃NH₃PbI₃(Cl) solar cells containing various amounts of NH₄Cl were fabricated by spin-coating. The microstructures of the resulting cells were investigated by X-ray diffraction, optical microscopy, and scanning electron microscopy. The current density–voltage characteristics of the cell were improved by adding an appropriate amount of NH₄Cl and air blowing, which increased the photoconversion efficiency to 14%. Microstructure analysis indicated that the perovskite layer contained dense grains with strong (100) orientation, as a result of NH₄Cl addition and air blowing. The ratio of the (100)/(210) reflection intensities for the perovskite crystals was 2000 times higher than that of randomly oriented grains. The devices were stable when stored in ambient air for two weeks.

Perovskite solar cells with dense grains with strong (100) orientation were developed by adding NH₄Cl and air blowing.