ITQ-37 a chiral zeolite framework following the SrSi2 net and containing 30-ring extra-large gyroidal channels
| Autor: | Sun, Junliang, Bonneau, Charlotte, Cantin Sanz, Angel, Corma Canós, Avelino, Díaz Cabañas, Mª José, Moliner Marin, Manuel, Zhang, Daliang, Li, Mingrun, Zou, Xiaodong |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: | |
| Zdroj: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia instname |
| Popis: | [EN] The synthesis of crystalline molecular sieves with pore dimensions that fill the gap between microporous and mesoporous materials is a matter of fundamental and industrial interest(1-3). The preparation of zeolitic materials with extralarge pores and chiral frameworks would permit many new applications. Two important steps in this direction include the synthesis(4) of ITQ-33, a stable zeolite with 18 x 10 x 10 ring windows, and the synthesis(5) of SU-32, which has an intrinsically chiral zeolite structure and where each crystal exhibits only one handedness. Here we present a germanosilicate zeolite (ITQ-37) with extralarge 30-ring windows. Its structure was determined by combining selected area electron diffraction ( SAED) and powder X-ray diffraction (PXRD) in a charge-flipping algorithm(6). The framework follows the SrSi2 (srs) minimal net(7) and forms two unique cavities, each of which is connected to three other cavities to form a gyroidal channel system. These cavities comprise the enantiomorphous srs net of the framework. ITQ-37 is the first chiral zeolite with one single gyroidal channel. It has the lowest framework density (10.3 T atoms per 1,000 angstrom(3)) of all existing 4-coordinated crystalline oxide frameworks, and the pore volume of the corresponding silica polymorph would be 0.38 cm(3) g(-1). This project is supported by the CICYT ( Project MAT 2006-14274-C02-01 and Prometeo 2008 GV), the Swedish Research Council (VR) and the Swedish Governmental Agency for Innovation Systems (VINNOVA). J.S. and C. B. are supported by post-doctoral grants from the Carl-Trygger and Wenner-Gren foundations respectively. M. M. thanks ITQ for a scholarship. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|