Diaphragm and preparation method and application thereof

The invention discloses a diaphragm and a preparation method and application thereof, and belongs to the technical field of water purification, the diaphragm comprises a base material and a hydrophobic layer, and the base material is a porous material; the hydrophobic layer is distributed on the surface of one side of the base material and is an alkyl hydrophobic layer. According to the diaphragm piece, the hydrophobic layer is arranged on the surface of one side of the porous base material, so that the formed diaphragm piece is permeable on one side and hydrophobic on the other side, water flow can pass through the permeable surface, water drops can be formed on the hydrophobic surface when the water flow is reverse, namely, the reverse flowing resistance of the water flow is increased, and the water flow is prevented from flowing reversely. Therefore, on the basis that the number of the diaphragm pieces is not increased, water flow reverse flow and water mixing can be effectively prevented, and therefore th