In situ synthesis of metal clusters encapsulated within small-pore zeolites via a dry gel conversion method. Issue 24 (12th April 2018)

• Record Type: Journal Article
• Authors: Yang, Xiaoli; Liu, Qinggang; Zhang, Yaru; Su, Xiong; Huang, Yanqiang; Zhang, Tao
• Is Part Of: Nanoscale. Volume 10:Issue 24(2018)
• Page Start: 11320
• Page End: 11327
• Publication Date: 2018-04-12
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c8nr00549d
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : We report here a facile strategy for encapsulating Pt clusters into MFI crystals via a dry gel conversion (DGC) method, by introducing Pt-immobilized Schiff-SiO2 as the silicon resource. Abstract : We report here a facile strategy for encapsulating Pt clusters into MFI crystals via a dry gel conversion (DGC) method, by introducing Pt-immobilized Schiff-SiO2 as the silicon resource. This protocol involves a solid phase transformation process for crystallization which occurs without significant deconstruction of the structure of the Pt-containing precursor. High-angle annular dark-field scanning transmission electron microscopy images indicate that most of the Pt clusters are less than 1 nm in size and located in defective channels or voids of MFI. Thanks to the encapsulation role, these Pt clusters are stable against sintering even after calcination at 500 °C and only grow up to ∼2.8 nm after calcination at 800 °C. The uniform pore structure of a zeolite endows the Pt@zeolite catalyst with shape-selectivity for hydrogenation and oxidation reactions over size differentiated analog substrates. This synthesis method is attainable for the embedment of stable metal clusters inside the small-pore MFI zeolite.