Localized basification of the mesopore walls as a route to high dispersion of supported-metal catalyst

초록

Development of a simple and scalable protocol for the high dispersion of supported metal nanoparticles is an important aspect in catalysis. Most water-soluble inorganic salts become insoluble when adding base into the aqueous solution; therefore, we have attempted to induce localized precipitation of inorganic species onto the mesopore walls via surface basification with ??Me4N+)(OH- ) or ?밡 H2 groups. Herein, we demonstrate that a high content (~30 wt.%) of Ni, Cu, SnO nanoparticles can be highly dispersed on the mesopore walls functionalized with ??Me4N+)(OH- ) or ?밡 H2 groups. As a result of high dispersion, the metal nanoparticles supported on mesoporous zeolites exhibited a high catalytic activity in CO2 methanation reaction. This strategy can be generalized to various supports, such as MFI zeolite nanosponges, a MCM-48 mesoporous silica, and a mesoporous alumina. We believed that the basic-surface induced precipitation would be an effective way to increase the metal-surface sites, and consequently, advanced catalytic function in a number of applications.