Geometrically Constrained Polymerization of Styrene Over Heterogeneous Catalyst Layer in Silica Nanotube Reactors

Synthesis of Hollow Silica Nanotubes from Linear Metallosupramolecular Polyelectrolytes and Their Application as Catalyst Supports for Hydrogenation

In this study, we report a facile templating method to construct hollow silica nanotubes. In particular, bis-terpyridine is used to coordinate metal ions to form polymeric bis-terpyridine-metal complexes that further self-assemble into tubular organogels in the presence of cetyltrimethylammonium bromide. The following silica deposition on organogels and subsequent calcination give metal oxide-doped hollow silica nanotubes (M_xO_y-HSNs). Facilitated by the high coordination stability constants of bis-terpyridine with metal ions, a series of metal ions, such as Fe, Ni, Cu, and Zn, could be used to form polymeric bis-terpyridine-metal complexes. The supported Pt/Fe_xO_y-HSNs exhibit good catalytic performance for hydrogenation of a series of substituted nitrobenzenes, showing that the obtained M_xO_y-HSNs could be used as catalyst supports due to their good textural properties.