Abstract: A method for reducing the metal content in a water source includes dissolving an amount of a solubilizing anion in a low grade water comprising one or more cations under conditions suitable to formed a suspension comprising insoluble solubilizing anion-cation complexes wherein the anion comprises; and separating the insoluble solubilizing anion-cation complexes from the suspension to obtain a higher grade water having a metal content reduced by from about 50% to about 100%.

Abstract: A method for ambient-temperature synthesis of a catalyst for water electrolysis by dissolving an amount of an Fe2+ source and optionally an amount of a salt of another divalent cation in deionized water at ambient temperature to form a solution, placing nickel (Ni) foam into the solution, whereby the Ni foam serves as a substrate and/or a Ni source for growth of the catalyst, leaving the Ni foam in the solution at ambient temperature for a time duration in a range of from about 0.5 hour to about 4 hours to provide a treated foam, during which time duration, the catalyst is grown on the substrate, and removing the treated foam from the solution after the time duration, wherein the treated foam comprises the catalyst grown thereon.