Provided herein is a method to printed electronics, and more particularly related to printed electronics on flexible, porous substrates. The method includes applying a coating compound comprising poly (4-vinylpyridine) (P4VP) and SU-8 dissolved in an organic alcohol solution to one or more surface of a flexible, porous substrate, curing the porous substrate at a temperature of at least 130° C. such that the porous substrate is coated with a layer of said coating compound, printing a jet of a transition metal salt catalyst solution onto one or more printing sides of the flexible, porous substrate to deposit a transition metal salt catalyst onto the one or more printing sides, and submerging the substrate in an electroless metal deposition solution to deposit the metal on the flexible, porous substrate, wherein the deposited metal induces the formation of one or more three-dimensional metal-fiber conductive structures within the flexible, porous substrate.