Immobilization of Metal Nanoparticles in Surface Layer of Silica Matrices

摘要

Gold and silver nanoparticles were obtained by in situ reduction with silicon hydride groups grafted to the mesoporous MCM-41 silica surface. Nickel-, cobalt-, and iron-containing silicas were synthesized by chemisorption of appropriate metal acetylacetonates with following reduction in the acetylene atmosphere. Such metal-containing MCM-41 matrices have been applied for preparation of carbon nanostructures at pyrolytic decomposition of acetylene. From transmission electron microscopy (TEM) data a lot of carbon nanotubes were formed, namely tubes with external diameter of 10-35 nm for Ni-, 42–84 nm for Co-, and 14–24 nm for Fecontaining silicas. In the metal absence on the silica surface low yield of nanotubes (up to 2%) was detected.