From Single Molecules to Nanoscopically Structured Materials: Self-Assembly of Metal Chalcogenide/Metal Oxide Nanostructures Based on the Degree of Pearson Hardness

A chemically specific and facile method for the immobilization of metal oxide nanoparticles onto the surface of IF-MoS2 nested fullerenes is reported. The modification strategy is based on the chalcophilic affinity of transition metals such as Fe2+/Fe3+, Fe3+, or Zn2+ as described by the Pearson HSAB concept. The binding capabilities of the 3d metals are dictated by their Pearson hardness. Pearson hard cations such as Fe3+ (Fe2O3) do not bind to the chalcogenide surfaces; borderline metals such as Fe2+ (Fe 3O4) or Zn2+ (ZnO) bind reversibly. Pearson-soft metals like Au bind irreversibly. The immobilization of metal oxide nanoparticle colloids was monitored by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) combined with energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). © 2011 American Chemical Society