Synthesis and Characterization of Supported Co₂P Nanoparticles by Grafting of Molecular Clusters into Mesoporous Silica Matrixes

High-quality Co 2 P nanoparticles have been obtained from diphosphine-substituted molecular cobalt clusters anchored into an inorganic matrix. The synthesis was followed stepwise using a wide panel of analytic techniques. The required functionalization of an ordered mesoporous silica matrix of the type SBA-15 was achieved by covalent attachment of the alkoxysilyl-substituted short-bite diphosphine ligand (Ph 2 P) 2 N(CH 2 ) 3 Si(OMe) 3 . Anchoring of the cluster [Co 4 (CO) 10 (μ-dppa)] (dppa = (Ph 2 P) 2 NH) led to an organometallic hybrid mesoporous silica whose thermal treatment led to pure nanocrystalline Co 2 P particles. Compared with the particles obtained in a silica xerogel, those synthesized into the SAB-15 matrix were the most regular in spatial repartition, size, and shape.