Show simple item record

dc.contributor.authorXia, Yongdeen_GB
dc.contributor.authorMokaya, Ren_GB
dc.date.accessioned2012-09-28T18:20:21Zen_GB
dc.date.accessioned2013-03-20T12:20:37Z
dc.date.issued2008-02en_GB
dc.description.abstractThe preparation, structural characterization, and catalytic evaluation of novel solid acid-base mesoporous aluminosilica oxynitride materials are presented in this report. The materials were prepared by subjecting both direct (mixed-gel) synthesized and postsynthesis Al-grafted aluminosilicate MCM-48 materials to high-temperature nitridation, i.e., treatment with ammonia at elevated temperature. The properties of the mesoporous aluminosilica oxynitrides are mainly dependent on the preparation method and Al content. In general, aluminosilicates with high Al content were more susceptible to structural degradation during nitridation. Directly synthesized samples suffered greater structural degradation compared to Al-grafted samples of similar Al content. Oxynitrides derived from directly synthesized Al-MCM-48 exhibited higher amounts of nitrogen compared to materials derived from Al-grafted MCM-48, and in all cases, the nitrogen was incorporated into the aluminosilicate frameworks to generate various NHx species, including terminal NH2 and bridging NH groups and ammonium ions. The relative amount of terminal NH2 and bridging NH groups was dependent on the Al content and preparation history. The aluminosilica oxynitride materials exhibit both acidic and basic surface functionalities. The amount of acid sites and basic sites can be adjusted by controlling the Al content and by tuning the nitridation conditions. Basic sites predominate in all the mesoporous MCM-48 aluminosilica oxynitride materials', and the basicity was demonstrated by catalytic activity for the Knoevenagel condensation reaction.en_GB
dc.identifier.citationVol. 112, Issue 5, pp. {1455-1462} - {1455-1462}en_GB
dc.identifier.doi10.1021/jp077578gen_GB
dc.identifier.urihttp://hdl.handle.net/10036/3809en_GB
dc.titleMesoporous MCM-48 aluminosilica oxynitrides: Synthesis and characterization of bifunctional solid acid-base materialsen_GB
dc.date.available2012-09-28T18:20:21Zen_GB
dc.date.available2013-03-20T12:20:37Z
dc.identifier.issn1932-7447en_GB
dc.descriptionnotes: unique-id: ISI:000252814800025en_GB
dc.descriptiontypes: Articleen_GB


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record