Controllable Encapsulation of 'Clean' Metal Clusters within MOFs through Kinetic Modulation: Towards Advanced Heterogeneous Nanocatalysts

摘要

Surfactant-free tiny Pt clusters were successfully encapsulated within MOFs with controllable size and spatial distribution by a novel kinetically modulated one-step strategy. Our synthesis relies on the rational manipulation of the reduction rate of Pt ions and/or the growth rate of MOFs by using H-2 as assistant reducing agent and/or acetic acid as MOF-formation modulator. The as-prepared Pt@MOF core-shell composites exhibited exceedingly high activity and excellent selectivity in the oxidation of alcohols as a result of the ultrafine clean Pt clusters, as well as interesting molecular-sieving effects derived from the outer platinum-free MOF shell.