Biemmi E, Bein T. Assembly of nanozeolite monolayers on the gold substrates of piezoelectric sensors.
LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008;
24:11196-11202. [PMID:
18729483 DOI:
10.1021/la8009892]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Colloidal zeolites NaA (LTA structure type) and ZSM-5 (MFI-type) with crystal diameters of about 100 nm were synthesized as building blocks for the formation of microporous self-limiting monolayers on the piezo-active area (gold electrodes) of a quartz crystal microbalance (QCM). Two different coupling strategies were explored, concerning the modification of either the gold substrate or the external zeolite crystal surface with a bifunctional molecular interface. Diverse analytical methods were employed to fully characterize the materials (dynamic light scattering, X-ray diffraction, infrared and Raman spectroscopy, solid state 29Si NMR spectroscopy, N2 sorption) and to study the process of coupling the zeolite crystals to the gold surface (reflection-absorption IR spectroscopy, scanning electron microscopy). The molecularly selective sensing behavior of these zeolite-coated devices is demonstrated by measuring the full adsorption isotherms of n-butane and i-butane in the microporous films.
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