Method of manufacturing an isolated porous material and an isolated porous material

Abstract

The present invention relates to a porous material comprising a porous wall structure defining and separating primary pores that are interconnected across its thickness dimension. The primary pores have a diameter greater than 5 μm and less than 1000 μm. The diameter of the primary pores gradually increases across its thickness dimension while their number decreases in its thickness dimension. The porous wall structure comprises or consists of secondary pores that are interconnected throughout the material. The secondary pores have a diameter smaller than 5 μm. The present invention further relates to a method of manufacturing an isolated porous material comprising the steps of: providing a substrate; applying an electrically conductive intermediate layer on at least part of a surface of the substrate; forming a surface layer on the intermediate layer by electrodeposition using dynamic bubble templating; and removing the intermediate layer from the porous surface layer to obtain the isolated porous material; wherein the step of removing the intermediate layer takes place during or after deposition of the porous surface layer. The present invention further relates to a porous material obtainable with a method of manufacturing according to the second aspect. The present invention further relates to the use of a porous material according to the first or third aspect in a chemical or electrochemical system.

1 . Porous material comprising a porous wall structure defining and separating primary pores that are interconnected across its thickness dimension, wherein the primary pores have a diameter greater than 5 μm and less than 1000 μm and wherein the diameter of the primary pores gradually increases across its thickness dimension while their number decreases in its thickness dimension, wherein the porous wall structure comprises or consists of secondary pores that are interconnected throughout the material, wherein the secondary pores have a diameter smaller than 5 μm, wherein the porous material is an isolated porous material. 
     
     
         2 . The porous material according to  claim 1 , wherein the material is foldable on itself without breaking, up to a bend radius equal to or below 2 mm. 
     
     
         3 . The porous material according to  claim 1 , wherein the material is permeable by gases and liquids continuously in all directions. 
     
     
         4 . The porous material according to  claim 1 , wherein the material has a porosity of at least 85%. 
     
     
         5 . The porous material according to  claim 1 , wherein the porous material has a surface area of at least 0.1 m 2 /g. 
     
     
         6 . The porous material according to  claim 1 , wherein the porous material has an in-plane resistivity of at most 10×10 −5  Ωm. 
     
     
         7 . The porous material according to  claim 1 , wherein the porous material is sintered. 
     
     
         8 . Method of manufacturing an isolated porous material according to  claim 1 , comprising the steps of:
 providing a substrate;   applying an electrically conductive intermediate layer on at least part of a surface of the substrate;   forming a porous surface layer on the intermediate layer by electrodeposition using dynamic bubble templating; and   removing the intermediate layer from the porous surface layer to obtain the isolated porous material; wherein the step of removing the intermediate layer takes place during or after deposition of the porous surface layer.   
     
     
         9 . The method according to  claim 8 , wherein the electro-deposited surface layer comprises a porous wall structure defining and separating primary pores that are interconnected in the general direction normal to the surface of the intermediate layer, wherein the primary pores have a diameter greater than 5 μm and less than 1000 μm and wherein the diameter of the pores gradually increases with distance from the intermediate layer. 
     
     
         10 . The method according to  claim 8 , wherein the intermediate layer is a metal with a lower standard electrode potential than the material of the surface layer. 
     
     
         11 . The method according to  claim 8 , wherein the step of removing the intermediate layer takes place after deposition of the porous surface layer, by slicing with a straight edge blade by etching with an acid or by dissolving in a solvent. 
     
     
         12 . The method according to  claim 8 , wherein the deposited material is a metallic material. 
     
     
         13 . The method according to  claim 8 , wherein the substrate and the surface layer comprise the same or different material. 
     
     
         14 . The method according to  claim 8 , wherein the deposition takes place using a solution comprising copper sulphate, and this solution is mixed with sulfuric acid. 
     
     
         15 . The method according to  claim 8 , wherein the potential during deposition is at least 4 V. 
     
     
         16 . The method according to  claim 8 , wherein the porous surface layer is Cu, and the deposition takes place using a solution of copper sulphate mixed with sulfuric acid, and wherein the intermediate layer is made of zinc and has a thickness between 200 nm and 500 nm. 
     
     
         17 . The method according to  claim 8 , wherein the porosity, binary pore size distribution and the pore-size gradient across the thickness dimension of the porous material are substantially unchanged by removal of the intermediate layer. 
     
     
         18 . The method according to  claim 8 , further comprising the steps of:
 washing the isolated porous material with a low surface tension liquid, and subsequently   optionally drying the isolated porous material; and/or   the method further comprising the step of:   sintering the isolated porous material by heat treatment.   
     
     
         19 . (canceled) 
     
     
         20 . Porous material obtainable with a method of manufacturing according to  claim 8 . 
     
     
         21 . Use of the porous material according to  claim 1  in a chemical or electrochemical system.