Methods of Forming a Metal Material from a Metal Oxide Material by Electrochemical Reduction and Related Systems and Articles

Abstract

A method of forming a metal material comprises exposing one or more metal oxide materials to one or more of a reducing agent and a reducing atmosphere to form one or more non-stoichiometric metal oxide materials and electrochemically reducing the one or more non-stoichiometric metal oxide materials to a metal material or a metal alloy. A system comprising one or more electrochemical cells and a working electrode comprising one or more non-stoichiometric metal oxide materials exhibiting an anion-deficient oxide structure is also disclosed, in addition to a metal material including a porous metal or a porous metal alloy that exhibits an oxygen content of less than or equal to about 1200 parts per million.

What is claimed is: 
     
         1 . A method of forming a metal material, comprising:
 exposing one or more metal oxide materials to one or more of a reducing agent and a reducing atmosphere to form one or more non-stoichiometric metal oxide materials; and   electrochemically reducing the one or more non-stoichiometric metal oxide materials to a metal material.   
     
     
         2 . The method of  claim 1 , wherein exposing one or more metal oxide materials to one or more of a reducing agent and a reducing atmosphere to form one or more non-stoichiometric metal oxide materials comprises exposing one or more of a group III metal oxide material, a group IV metal oxide material, a transition metal oxide material, a lanthanide oxide material, and an actinide oxide material to the one or more of the reducing agent and the reducing atmosphere. 
     
     
         3 . The method of  claim 1 , wherein exposing one or more metal oxide materials to one or more of a reducing agent and a reducing atmosphere to form one or more non-stoichiometric metal oxide materials comprises exposing one or more of an aluminum oxide, a chromium oxide, a nickel oxide, a silicon oxide, a germanium oxide, a hafnium oxide, a vanadium oxide, a chromium oxide, an iron oxide, a neodymium oxide, a cerium oxide, a cobalt oxide, a magnesium oxide, a molybdenum oxide, a niobium oxide, a platinum oxide, a tantalum oxide, a titanium oxide, a tungsten oxide, a zinc oxide, a zirconium oxide, a lanthanum oxide, a praseodymium oxide, a samarium oxide, a europium oxide, a gadolinium oxide, a terbium oxide, a dysprosium oxide, a holmium oxide, an erbium oxide, a thulium oxide, a ytterbium oxide, a lutetium oxide, a uranium oxide, a plutonium oxide, and a thorium oxide to the one or more of the reducing agent and the reducing atmosphere. 
     
     
         4 . The method of  claim 1 , wherein exposing one or more metal oxide materials to a reducing agent comprises combining the one or more metal oxide materials and a reducing agent comprising a hydride compound. 
     
     
         5 . The method of  claim 4 , wherein combining the one or more metal oxide materials and a reducing agent comprising a hydride compound comprises combining the one or more metal oxide materials with one or more of gallium hydride, vanadium hydride, chromium hydride, titanium hydride, and zirconium hydride. 
     
     
         6 . The method of  claim 1 , wherein exposing one or more metal oxide materials to a reducing atmosphere comprises exposing the one or more metal oxide materials to hydrogen gas or a combination of hydrogen gas and an inert gas. 
     
     
         7 . The method of  claim 1 , wherein exposing one or more metal oxide materials to a reducing atmosphere comprises exposing the one or more metal oxide materials to hydrogen gas, a combination of hydrogen gas and argon, or a combination of hydrogen gas and helium to form one or more metal oxide materials exhibiting an anion-deficient oxide structure. 
     
     
         8 . The method of  claim 7 , wherein exposing the one or more metal oxide materials to hydrogen gas, a combination of hydrogen gas and argon, or a combination of hydrogen gas and helium to form one or more metal oxide materials exhibiting an anion-deficient oxide structure comprises exposing the one or more metal oxide materials to hydrogen gas, a combination of hydrogen gas and argon, or a combination of hydrogen gas and helium in a static bed reactor. 
     
     
         9 . The method of  claim 7 , wherein exposing the one or more metal oxide materials to hydrogen gas, a combination of hydrogen gas and argon, or a combination of hydrogen gas and helium to form one or more metal oxide materials exhibiting an anion-deficient oxide structure comprises exposing the one or more metal oxide materials to hydrogen gas, a combination of hydrogen gas and argon, or a combination of hydrogen gas and helium in a fluidized bed reactor. 
     
     
         10 . The method of  claim 1 , further comprising selecting the one or more metal oxide materials to exhibit an open crystal structure. 
     
     
         11 . The method of  claim 1 , wherein exposing the one or more metal oxide materials to a reducing atmosphere comprises combining the one or more metal oxide materials and a fugitive agent and exposing the one or more metal oxide materials and the fugitive agent to the reducing atmosphere. 
     
     
         12 . The method of  claim 10 , wherein combining the one or more metal oxide materials and a fugitive agent comprises combining the one or more metal oxide materials with a fugitive comprising one or more of a metal carbonate or a metal oxalate. 
     
     
         13 . The method of  claim 1 , wherein electrochemically reducing the one or more non-stoichiometric metal oxide materials to a metal material comprises forming a metal or a metal alloy. 
     
     
         14 . A system, comprising:
 one or more electrochemical cells comprising:
 a counter electrode; 
 a working electrode in electrical communication with the counter electrode and comprising one or more non-stoichiometric metal oxide materials exhibiting an anion-deficient oxide structure; 
 an electrolyte comprising a molten salt, the counter electrode and the working electrode disposed in the electrolyte; and 
 a power source electrically coupled to the counter electrode and the working electrode and configured to provide a current flow between the counter electrode and the working electrode. 
   
     
     
         15 . The system of  claim 14 , wherein the working electrode comprising the one or more non-stoichiometric metal oxide materials comprises one or more of a group III metal oxide material, a group IV metal oxide material, a transition metal oxide material, a lanthanide oxide material, and an actinide oxide material. 
     
     
         16 . The system of  claim 14 , wherein the working electrode comprises a non-stoichiometric titanium oxide or a non-stoichiometric tantalum oxide. 
     
     
         17 . The system of  claim 14 , wherein the working electrode comprising the one or more non-stoichiometric metal oxide materials exhibits a porosity of from about 10% to about 60%. 
     
     
         18 . A metal article, comprising:
 a porous metal or a porous metal alloy exhibiting an oxygen content of less than or equal to about 1200 parts per million.   
     
     
         19 . The metal article of  claim 18 , wherein the porous metal or the porous metal alloy comprises interconnected pores extending through the metal article. 
     
     
         20 . The metal article of  claim 18 , wherein the porous metal or porous metal alloy exhibits a porosity of from about 10% to about 50% of a total volume of the metal article, and a metal of the porous metal or porous metal alloy comprises one or more of aluminum, chromium, hafnium, neodymium, cerium, cobalt, magnesium, molybdenum, niobium, neodymium, platinum, tantalum, titanium, tungsten, zinc, zirconium, a combination thereof, or an alloy thereof.