Methods for preparing and using metal and/or metal oxide porous materials

A method for producing a metal and/or metal oxide hierarchically porous body, comprising:

• (i) contacting a monolithic hierarchically porous template and a neat metal salt or metal salt hydrate to form a mixture, wherein the neat metal salt or metal salt hydrate has a decomposition temperature and a melting temperature, and wherein the neat metal salt or metal salt hydrate is heated to a temperature above the melting temperature of the neat metal salt or metal salt hydrate, but below the decomposition temperature of the neat metal salt or metal salt hydrate;
• (ii) maintaining the mixture at a temperature above the melting temperature of the neat metal salt or metal salt hydrate, but below the decomposition temperature of the neat metal salt or metal salt hydrate until a desired spatial distribution of the neat metal salt or metal salt hydrate in the monolithic hierarchically porous template is obtained;
• and then
• (iii) heating the mixture to above the decomposition temperature of the neat metal salt or metal salt hydrate in the presence of a reducing agent or inert atmosphere to produce the metal and/or metal oxide hierarchically porous material;
• and
• optionally repeating steps (i)-(iii) with the same neat metal salt or metal salt hydrate or with a different neat metal salt or metal salt hydrate.