Porous Materials

Abstract

A porous membrane material comprising a porous membrane substrate coated with a thin, uniform coating of a metal or metal alloy. The membrane material can have high electrical conductivity. The membrane material can exhibit a very high ratio of electrical conductivity to thermal conductivity. The porous membrane substrate may be removed to form the membrane.

1 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin and uniform coating of one or more metals or metal alloys, the coating having a thickness that falls in the range from ˜10 nm to ˜1 μm, wherein the coating extends all through the thickness of the porous material and wherein the coating imparts high conductivity to the membrane such that the porous material has an equivalent conductivity of from 0.05 S/cm to 440,000S/cm and wherein the porous material has a volume fraction of solid of less than 80%. 
     
     
         2 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin, uniform coating of one or more metals or metal alloys, the coating having a thickness that falls in the range from ˜10 nm to ˜1 μm, wherein the coating extends all through the thickness of the porous material and wherein the coating imparts high conductivity to the membrane such that the porous material has an equivalent conductivity of from 10 to 440,000S/cm and wherein the porous material has a volume fraction of coating of less than 80%. 
     
     
         3 . A porous material as claimed in  claim 1  wherein an equivalent conductivity of the porous material is at least ˜0.016% of that obtained for thin films of similar composition and thickness deposited on solid substrates. 
     
     
         4 . A porous material as claimed in  claim 1  wherein an equivalent conductivity of the porous material is 0.0065% or greater than that obtained for solid materials of similar composition, or ˜ 1/50 th  or greater than that obtained for solid materials of similar composition, or ˜ 1/20 th  or greater than that obtained for solid materials of similar composition, or ˜ 1/10 th  or greater than that obtained for solid materials of similar composition, or ˜⅕ th  or greater than that obtained for solid materials of similar composition, or ½ or greater than that obtained for solid materials of similar composition. 
     
     
         5 . A porous material as claimed in  claim 1  wherein an equivalent solid conductivity of the porous material ranges from about 10 S/cm to 281000 S/cm, or from10 S/cm to 1500 S/cm, or 100 S/cm to 1500 S/cm. 
     
     
         6 . A porous material as claimed in  claim 1  wherein the one or more metals or metal alloys is selected from the group consisting of copper, tin, nickel, iron, aluminum, titanium, cobalt, zinc, manganese, silver, gold, antimony, cadmium, tellurium, bismuth, platinum, palladium, ruthenium, rhodium, chromium, magnesium, calcium, beryllium, zirconium, molybdenum, lead, vanadium, potassium, niobium, cadmium, iridium, osmium, rhenium, indium, gallium, germanium, thallium, selenium and alloys thereof, and alloys comprising SnNi, SnFe, SnBi, SnSe, SnSb, SnSbNi, SnSbCo, CuSn, CuZn, Mg 2 Si, MnSn, MgSn, alloys based on the combination of titanium and aluminum. 
     
     
         7 . A porous material as claimed in  claim 1  wherein the material is post-treated to add additional functionality. 
     
     
         8 . A porous material as claimed in  claim 1  wherein the different material of the coating comprises nanoparticles such that the nanoparticles are applied to a surface of the substrate. 
     
     
         9 . A porous material as claimed in  claim 1  wherein the coating comprises nanolayers of the different material. 
     
     
         10 . A porous material as claimed in  claim 9  wherein the coating comprises a plurality of nanolayers. 
     
     
         11 . A porous material as claimed in  claim 1  wherein the porous material has a ratio of compressive strength (measured in Mpa) to volume fraction of solids (measured as volume fraction) of greater than 5 Mpa/v f , or greater than 10 MPa/v f , or greater than 50 MPa/v f , or greater than 100 MPa/v f . 
     
     
         12 . A porous material as claimed in  claim 1  wherein a thin layer of solid material is placed on top of the uniform coating, to provide a contacting surface. 
     
     
         13 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin, uniform coating of a one or more metals or metal alloys wherein the coating extends all through the thickness of the porous material and wherein the coating imparts high conductivity to the membrane and wherein the porous material has a volume fraction of solid of less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5% wherein the porous material has a ratio of compressive strength (measured in Mpa) to volume fraction of solids (measured as volume fraction) of greater than 5Mpa/v f , or greater than 10 MPa/v f , or greater than 50 MPa/v f , or greater than 100 MPa/v f . 
     
     
         14 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin, uniform coating of one or more metals or metal alloys wherein the coating extends all through the thickness of the porous material and wherein the coating imparts an equivalent solid conductivity in the range of 0.05 S/cm to 440,000 S/cm to the membrane and wherein the porous material has a volume fraction of solid of less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         15 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin, uniform coating of one or more metals or metal alloys wherein the coating extends all through the thickness of the porous material and wherein the coating imparts an equivalent solid conductivity in the range of 0.05 S/cm to 1500 S/cm to the membrane and wherein the porous material has a volume fraction of coating of less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         16 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin uniform coating of one or more metals or metal alloys, the coating having a thickness that falls within the range of from ˜10 nm to ˜200 nm wherein the coating extends all through the thickness of the porous material and wherein the coating imparts an equivalent solid conductivity in the range of 0.05 S/cm to 1500 S/cm to the membrane and wherein the porous material has a volume fraction of solid of less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         17 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin uniform coating of a different material, the coating having a thickness that falls within the range of from ˜10 nm to ˜200 nm wherein the coating extends all through the thickness of the porous material and wherein the coating imparts an equivalent solid conductivity in the range of 0.05 S/cm to 1500 S/cm to the membrane and wherein the porous material has a volume fraction of coating of less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         18 . A porous material as claimed in  claim 1  wherein the coating has a thickness that falls in the range of from ˜10 nm to ˜860 nm, or from ˜10 nm to ˜300 nm, or from ˜10 nm to ˜280 nm, or from ˜10 nm to -260 nm, or from ˜10 nm to ˜200 nm. 
     
     
         19 . A porous material as claimed in  claim 1  wherein the coating further comprises sulfur. 
     
     
         20 . A porous material as claimed in  claim 19  wherein the sulfur is present as a distinct layer. 
     
     
         21 . A porous material as claimed in  claim 19  wherein the sulfur is intimately mixed with one or more of the metals or metal alloys. 
     
     
         22 . A porous material as claimed in  claim 1  wherein the one or more metal alloys contain cobalt and one or more other metals. 
     
     
         23 . A porous material as claimed in  claim 1  wherein the volume fraction of solid is less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         24 . A porous material as claimed in  claim 2  wherein the volume fraction of solid is less than 50%, or less than 40%, or less than 30%, or less than 25% or less than 5.5%. 
     
     
         25 . A porous material as claimed in  claim 6  wherein the one or more metals or metal alloys are selected from copper, tin, nickel, iron, aluminium, titanium, cobalt, zinc, manganese, silver, gold, and alloys thereof. 
     
     
         26 . A porous material comprising a porous polymeric membrane substrate having a pore size in a range from 0.1 μm to 10 μm and coated with a thin and uniform coating of one or more metal phosphides, the coating having a thickness that falls in the range from ˜10 nm to ˜1 μm, wherein the coating extends all through the thickness of the porous material and wherein the coating imparts high conductivity to the membrane such that the porous material has an equivalent conductivity of from 0.05 S/cm to 440,000 S/cm and wherein the porous material has a volume fraction of solid of less than 80%. 
     
     
         27 . A porous material as claimed in  claim 26  wherein the one or more metal phosphides are selected from one or more of copper phosphide, iron phosphide, tin phosphide, and nickel phosphide.