Monodispersed Ag Nanoparticles as Catalyst: Preparation Based on Crystalline Supramolecular Hybrid of Decamethylcucurbit[5]uril and Silver Ions

Monodispersed
silver nanoparticles (Ag0 NPs) have been first prepared
on the basis of a postsynthesis via mild reduction from a new crystalline
supramolecular hybrid solid assembled from Ag+ ions and
decamethylcucurbit[5]­uril (Me10CB­[5]). Uniform growth of
nearly spherical Ag0 NPs with an average size of ca. 4.4
nm was observed on the organic Me10CB­[5] support to form Ag@Me10CB­[5] composite
material. The as-synthesized composite material was characterized
by a range of physical measurements (PXRD, TGA, XPS, ICP, TEM, etc.)
and was further exploited as a heterogeneous catalyst for the reduction
of various nitrophenols in the presence of NaBH4. The kinetics
of the reduction process was monitored under various experimental
conditions. The Ag@Me10CB­[5] composite material showed excellent catalytic performance
over the reduction reactions and remained active after several consecutive
cycles.