Perovskite thin film, organic solvent-free perovskite thin film preparation method and application thereof

The invention discloses a perovskite thin film, and a preparation method and application of the perovskite thin film without participation of an organic solvent. The perovskite thin film preparation method without participation of the organic solvent comprises the steps that ABX3 powder is evenly dispersed on the surface of a base material, A < + > in ABX3 comprises MA < + >, FA < + >, Cs < + > or Bi < + >, B < 2 + > in ABX3 comprises Pb < 2 + > or Sn < 2 + >, and X in ABX3 comprises Cl , Br or I ; enabling alkaline gas to be in contact with the ABX3 powder, so that the ABX3 powder is dissolved, and a uniform ionic liquid film is formed on the surface of the base material; and removing the alkaline gas in the ionic liquid film so as to prepare the perovskite thin film. According to the method, the use of an organic solvent can be avoided in the film forming process, alkaline gas in the ionic liquid can be quickly removed by utilizing the volatility of gas and annealing, the compactness of the pr