Planar heterojunction perovskite solar cell and preparation method thereof

The invention belongs to the technical field of solar cells and specifically discloses a planar heterojunction perovskite solar cell and a preparation method thereof. The planar heterojunction perovskite solar cell comprises a transparent conductive electrode, an electron transmission layer, a perovskite luminous absorption layer, a cavity transmission layer and a method electrode in sequence from down to up. The electron transmission layer is a TiO2 compact layer. The perovskite luminous absorption layer is made of a chloride-ion-doped perovskite material. According to the invention, a TiO2 mesoporous layer in a conventional sensitized solar cell is rejected, and the device structure and the preparation technology are simplified; the chloride-ion-doped perovskite material is used as the luminous absorption material, the film forming ability of a film is improved, and the diffusion and separation of carriers are facilitated; aimed at the processing of the transparent conductive electrode and the TiO2 compact layer, an oxygen plasma processing technology is provided, and the film forming effect is improved; and aimed at the thickness control problem of the perovskite luminous absorption layer, a layer-by-layer spin coating technology is adopted, and the photoelectric performance of the luminous absorption layer and the integral cell is regulated and controlled.