title: Structural diversity of lamellar zeolite Nu-6(1)--postsynthesis of delaminated analogues.
abstract: Nu-6(1) zeolite, the lamellar precursor of NSI topology, was firstly synthesized with 4'4-bipyridine as the structure-directing agent (SDA) and then subjected to HCl-EtOH treatment for the purpose of structural modification. Interlayer deconstruction and reconstruction took place alternately in this acid treatment. An intermediate named ECNU-4 was separated at the initial stage of this continuous treatment process, which exhibited a special X-ray diffraction pattern without obvious reflection peaks at low angles. The zeolitic structure in the intralayer sheets was supposed to be well preserved in ECNU-4, whereas the interlayer structure became extremely disordered. The ECNU-4 intermediate showed structural diversity. It was converted into the reconstructed and interlayer expanded zeolite IEZ-NSI without an external silicon source by prolonging the HCl-EtOH treatment to 24 h. Moreover, with a partially delaminated structure, ECNU-4 was easily interlayer swollen at room temperature with cetyltrimethyl ammonium bromide in the presence of tetrapropyl ammonium hydroxide. The swollen material was further sonicated to yield a more deeply delaminated zeolite, Del-Nu-6. ECNU-4 and Del-Nu-6 differed in delamination degree, structural disordering and textural properties, especially surface area.
authors.affiliation: Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, China. pwu@chem.ecnu.edu.cn hhwu@chem.ecnu.edu.cn.
authors.forename: Hao
authors.initials: H
authors.lastname: Xu
authors.forename: Lili
authors.initials: L
authors.lastname: Jia
authors.forename: Haihong
authors.initials: H
authors.lastname: Wu
authors.forename: Boting
authors.initials: B
authors.lastname: Yang
authors.forename: Peng
authors.initials: P
authors.lastname: Wu