Three dimensional nano-porous film and fabrication method thereof

A method for fabricating nanoporous film, comprising:

• providing a substrate with a surface;
• forming a coating of a composition on the surface, the composition comprising the following components as a uniform solution in a first organic solvent:
• an oxide gel in an amount of 45 to 95 parts by weight, wherein the oxide gel comprises condensation products of at least one oxide gel precursor, and the at least one oxide gel precursor comprises a first oxide gel precursor having a formula (I), of
• n(R1)—M(OR2)m
• wherein n and m are an integer equal to or more than 1, and the sum of n and m is equal to or more than 2;
• M is element of Group IIIB, element of Group IVB, element of Group VB, or transition metal;
• Rl is alkenyl group, acrylic group, acryloyl group, amine group, alkoxy group, or isocyanato group;
• and R2 is alkyl group or haloalkyl group;
• a non-reactive polymer template in an amount of 5 to 55 parts by weight;
• and
• an initiator in an amount of 1 to 10 parts by weight, based on 100 parts by weight of the oxide gel and the template;
• curing the coating to condense and polymerize the oxide gel, thereby forming an organic/inorganic hybrid film and inducing a phase separation between polymer template and the condensed and polymerized oxide gel;
• and
• dissolving the polymer template from the organic/inorganic hybrid film by a second organic solvent to leave the nanoporous film with three-dimensional nanopores.