Co(2+)@Mesoporous Silica Monoliths: Tailor-Made Nanoreactors for Confined Soft Chemistry

Chemistry. 2015 Nov 16;21(47):16906-16. doi: 10.1002/chem.201501918. Epub 2015 Oct 2.


Mesoporous silica monoliths with various ordered nanostructures containing transition metal M(2+) cations in variable amounts were elaborated and studied. A phase diagram depicting the different phases as a function of the M(2+) salt/tetramethyl orthosilicate (TMOS) and surfactant P123/TMOS ratios was established. Thermal treatment resulted in mesoporous monoliths containing isolated, accessible M(2+) species or condensed metal oxides, hydroxides, and salts, depending on the strength of the interactions between the metal species and the ethylene oxide units of P123. The ordered mesoporosity of the monoliths containing accessible M(2+) ions was used as a nanoreactor for the elaboration of various transition metal compounds (Prussian blue analogues, Hofmann compounds, metal-organic frameworks), and this opens the way to the elaboration of a large range of nanoparticles of multifunctional materials.

Keywords: cobalt; mesoporous materials; nanoparticles; phase diagrams; silica.