Formation of Crystalline Nanoclusters of Fe₂P, RuP, Co₂P, Rh₂P, Ni₂P, Pd₅P₂, or PtP₂ in a Silica Xerogel Matrix from Single-Source Molecular Precursors

Metal complexes containing bifunctional phosphine ligands that possess alkoxysilyl functional groups have been prepared for seven metals of the first, second, or third transition metal series. Incorporation of these single-source precursors into silica xerogel matrixes using sol-gel chemistry affords molecularly doped xerogels. Subsequent thermal treatment of these doped xerogels under solely reducing conditions selectively affords nanoclusters of Fe₂P, RuP, Co₂P, Rh₂P, Ni₂P, Pd₅P₂, or PtP₂ which are highly dispersed throughout the bulk of the xerogel matrix. Characterization of these nanocomposite materials by transmission electron microscopy, energy-dispersive spectrometry, X-ray diffraction, and electron diffraction indicates that the metal phosphide nanoclusters are highly crystalline with some exhibiting nonspherical morphology.