The SEA method can be extended to the synthesis of bimetallics and may
represent a simpler, more versatile alternative to surface redox reactions. The syntheses
of bimetallics are the same as described in the previous section, only that the
adsorbing supported oxide, like the CO3O4 depicted in Figure 13.13, is itself reducible
and, after reduction, forms a bimetallic particle in intimate contact with the
second metal precursor that had adsorbed directly onto it. This process can be
conducted at ambient conditions, with an intermediate calcination in air to create
the first metal oxide from a deposited or adsorbed precursor. The first metal might
itself be deposited by SEA in well-dispersed form by precursors such as cationic
cobalt hexa-ammine on silica. Thus, there is the potential to create homogeneous
bimetallic particles with very high dispersion, using simple methods with common
metal precursors