Macroporous materials from crystalline single-source precursors through decomposition followed by selective leaching

Abstract

There are a number of pairs of elements A and B in the periodic table that do not form binary oxides AxByO. We have used this fact to seek out crystalline precursors containing such metals that can be decomposed at elevated temperatures to form intimate mixtures of the individual oxides, AxO and ByO. Selective leaching of one of these oxide components from the monolithic mixture results in a macroporous material. We demonstrate this scheme by decomposing a hydroxy double salt containing Ni and Zn. The ZnO from the decomposition product can be leached out, leaving behind a macroporous NiO monolith that can be further reduced to yield porous metallic Ni.