Polyethyleneimine diaphragm for preparing hydrogen for fuel cell, and preparation method thereof

The invention belongs to the technical field of fuel cells, and provides a polyethyleneimine diaphragm for preparing hydrogen for a fuel cell, and a preparation method thereof. The method comprises the following steps: grafting a silicon base on polyethyleneimine, then forming a sol with polyvinyl alcohol under an acidic condition, converting the sol into a gel material, forming a film on the surface of an asbestos diaphragm, putting the film into a methyl alcohol solution containing methyl bromide, and curing to obtain the silicon dioxide modified polyethyleneimine diaphragm. Compared with atraditional method, the preparation method of the invention has the following characteristics that the silicon dioxide modified polyethyleneimine diaphragm prepared by the method has the advantages that inorganic silicon dioxide is formed by removing methyl from organic silicon, so that the hydrophilic performance of a diaphragm material is improved, the selective permeability to OH is improved, the performance is stab