Release Time:2019-03-13  Hits:

Indexed by: Journal Article

Date of Publication: 2016-08-01

Journal: ACS NANO

Included Journals: Scopus、PubMed、EI、SCIE

Volume: 10

Issue: 8

Page Number: 7401-7408

ISSN: 1936-0851

Key Words: hollow nanovesicle; multilevel structure; zeolite; metal-encapsulated; phenol degradation

Abstract: Inspired by the vesicular structure of alveolus which has a porous nanovesicle structure facilitating the transport of oxygen and carbon dioxide, we designed a hollow nanovesicle assembly with metal-encapsulated hollow zeolite that would enhance diffusion of reactants/products and inhibit sintering and leaching of active metals. This zeolitic nanovesicle has been successfully synthesized by a strategy which involves a one-pot hydrothermal synthesis of hollow assembly of metal-containing solid zeolite crystals without a structural template and a selective desilication-recrystallization accompanied by leaching-hydrolysis to convert the metal-containing solid crystals into metal-encapsulated hollow crystals. We demonstrate the strategy in synthesizing a hollow nanovesicle assembly of Fe2O3-encapsulated hollow crystals of ZSM-5 zeolite. This material possesses a microporous (0.4-0.6 nrn) wall of hollow crystals and a mesoporous (5-17 mu) shell of nanovesicle with macropores (about 350 mu) in the core. This hierarchical structure enables excellent Fe2O3 dispersion (3-4 nm) and resistance to sintering even at 800 degrees C; facilitates the transport of reactant/products; and exhibits superior activity and resistance to leaching in phenol degradation. Hollow nanovesicle assembly of Fe-Pt bimetal-encapsulated hollow ZSM-5 crystals was also prepared.