Method for preparing compact textured copper-indium-selenium film by indium selenide and copper ion composite technology

The invention discloses a method for preparing a compact textured copper-indium-selenium film by an indium selenide and copper ion composite technology. The method comprises the following steps: dispersing a prepared In2Se3 nanosheet in absolute ethyl alcohol to obtain nano ink, and carrying out complexation reaction on 2-amino-2-methyl-1-propanol serving as a complexing agent and CuCl to enhancethe solubility of copper ions; mixing the In2Se3 nano ink with a copper ion solution according to a ratio to form the CIS precursor uniform ink; depositing ink on a substrate through a dip-coating process, arranging nanosheets in the ink in an oriented mode in the deposition process, forming a precursor layer, and enabling the precursor layer to react in the selenylation sintering process: a Se liquid phase is decomposed after a copper-selenium compound is generated, mass transfer is promoted through the liquid phase, and the indium-selenium compound and the copper-selenium compound are combined into copper-indium-sel