Millimeter‐Sized Hierarchical Porous Titanosilicate Supported Ultrafine Ag Nanoparticles as Highly Efficient Catalyst

Abstract

Developing easily recyclable noble metal nanoparticle-based heterogeneous catalysts is highly desirable for the practical applications. Herein, a millimeter-sized hierarchical porous titanosilicate (HPTS) was prepared by the multi-template method. Various characterization results reveal that HPTS combines the structural advantages of monolith materials and nanomaterials. HPTS is used as an advanced support to construct the Ag/HPTS catalysts via the Ag + in situ reduction on its pore wall. Ag/HPTS shows high catalytic activity for 4-nitrophenol (4-NP) reduction with the TOF values of 3.91 min À 1 , which can be attributed to the ultrafine Ag NPs (2.04 nm) and the unique structure of HPTS. The 3D pass-through macroporous channels facilitate mass transfer. The mesopores with ultra-short channel remarkably enhance the accessibility of the active sites. The abundant mesopores and micropores effectively confine the Ag NPs size. Moreover, Ag/HPTS demonstrated good stability and recyclability.