Syntheses, structure solutions, and catalytic performance of two novel layered silicates
Number of Authors: 10
2015 (English)In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 44, no 35, 15567-15575 p.Article in journal (Refereed) Published
Two novel layered silicates, PKU-13 and PKU-13a, were hydrothermally synthesized by using trimethyl-propylammonium hydroxide as the structure directing agent (SDA). Their structures were solved by using powder X-ray diffraction data in combination with electron diffraction technique and NMR spectroscopy. These two silicates are built from the same r52 layer in different stacking modes: the adjacent r52 layers in PKU-13a have a 0.5b + 0.68c shift compared with those in PKU-13. The difference is due to the SDA cations located between the layers. The SDA cations exist as a monolayer in the structure of PKU-13, and link the adjacent layers by Coulomb actions in combination with strong hydrogen bonds. In PKU-13a, the SDA cations present in the bi-layer expend the distance between layers and destroy the inter-layer hydrogen bonds. PKU-13a can transform to PKU-13 after treatment with acetic acid solution. The co-existence of intra-layer hydrogen bonds in PKU-13 interfere in its condensation to an ordered crystalline microporous framework. Both PKU-13 and PKU-13a exhibit good catalytic activities as base catalysts in the Knoevenagel condensation reaction.
Place, publisher, year, edition, pages
2015. Vol. 44, no 35, 15567-15575 p.
IdentifiersURN: urn:nbn:se:su:diva-121191DOI: 10.1039/c5dt00487jISI: 000360452600028OAI: oai:DiVA.org:su-121191DiVA: diva2:857395