TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The method further involves coating the substrate with a binder material prior to the electrospraying step. The electrospraying is carried out at field strength of 0.2-4 kV/cm. The metal or metal oxide makes up 0.5-20 wt.% of the total suspension weight. The process (P1) further involves modifying the matrix by treatment with a silica-containing binder solution; washing the matrix with a solvent selected from deionized water and non-aqueous polar solvents prior to the modification step in order to enhance the wetting of conventional filter fiber materials. The modification step involves coating the matrix with a binder solution containing at least one silica-containing binder. Preferred Components: The metal or metal oxide particles have a particle diameter of not greater than 100 nm. The metal oxide is a photocatalytic material. The metal or metal oxide is selected from titanium dioxide (TiO2), zinc oxide (ZnO), zirconium oxide (ZrO2), calcium oxide (CaO), magnesium oxide (MgO), iron oxide (FeO), Fe2O3, vanadium pentaoxide (V2O5), manganese trioxide (Mn2O3), aluminum trioxide (Al2O3), nickel oxide (NiO), copper oxide (CuO), silicon dioxide (SiO2), silver (Ag), zinc (Zn), and/or copper (Cu), (preferably TiO2). The metal oxide suspension further comprises a sufficient amount of at least one chelating agent to enhance the dispersion of metal oxide particles in the suspension. The matrix comprises woven or nonwoven conventional fabrics. The binder is selected from tetraethyl orthosilicate, tetramethyl orthosilicate, tetra-n-propoxysilane, tetra-n-butoxysilane, and tetrakis(2-methoxyethoxy)silane, and organoalkoxysilanes such as methyltriethoxysilane, methyltrimethoxysilane, methyl tri-n-propoxysilane, phenytriethoxysilane, vinyltriethoxysilane and/or their mixtures. The binder solution further comprises an inorganic acid. The metal oxide suspension further comprises a sufficient amount of at least one chelating agent to enhance the dispersion of metal oxide particles in the suspension.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polymer used for electrospinning is selected from polyamide 11, polyamide 12, poly(vinyl acetate), poly (vinylidene fluoride), polyvinylpyrrolidone), poly(ethylene oxide), poly(acrylonitrile), poly(caprolactone), or poly(methyl methacrylate). In the material (M1), the fibers are fabricated from a polymer selected from polyamides, poly(vinyl acetate), poly(vinylidene fluoride), polyvinylpyrrolidone), poly(ethylene oxide), poly(acrylonitrile), poly(caprolactone), and/or poly(methyl methacrylate). The substrate, and/or the fibers are coated with a binding material. The binding material is hydrophilic. EXAMPLE - Titania deposited nanofibrous material was synthesized as follows: a polypropylene filter substrate was washed and cleaned by dipping into a deionized water and polar solvent mixture. It was subsequently dried at ambient temperature before dip coated in a silica binder solution. The substrate was then ultrasonicated and dried in an oven at 50-70 degrees C. A solution of polyamide 11 (2 grams) in formic acid/dichloromethane (48 g/30 ml) equal volume amount was prepared. The solution was heated on a heating plate while stirring. The polyamide solution was then electrospun onto the silica coated substrate at applied electric field strength of 1-30 kV, to produce polyamide nanofibers.