One-step synthesis of nano-size iron oxide /three-dimensional wormlike hierarchical mesoporous SiO_2 catalysts and its catalytic performance on phenol hydroxylation

摘要

A series of nano-sized iron oxide supported on 3D wormlike hierarchical mesoporous SiO_2 catalysts were synthesized by one-step hydrothermal synthesis. The samples were characterized by XRD, N_2 sorption, FT-IR, UV-Vis, TEM and ICP-AES. The catalysts were probed for the oxidation of phenol employing hydrogen peroxide. The results indicate that the materials exhibit high surface area and 3D wormlike hierarchical pore, iron ions exist as isolated framework species when the weight percentage content of iron is below 0.24 and nano-size iron oxide is dispersed in the surface (iron content above 0.24 wt%). Catalytic performance indicates that nano-size iron oxide supported on SiO_2 is useful to enhance both the catalytic activity and the selectivity of target products compared with isolated iron species.