Optical, structural and adsorption properties of zinc peroxide/hydrogel nanohybrid films

Department of Physical Chemistry and Materials Sciences, University of Szeged, H-6720 Szeged, Hungary
Applied Surface Science (Impact Factor: 2.71). 06/2010; 256(17):5349-5354. DOI: 10.1016/j.apsusc.2009.12.075


Hybrid nanofilms from zinc-peroxide/poly(acrylamide) (ZnO2/PAAm) and zinc-peroxide/poly(N-isopropyl-acrylamide) (ZnO2/PNIPAAm) were prepared using the photopolymerization procedure. The thin layers were prepared by the combination of the Layer-by-Layer (LbL) self-assembly method and photopolymerization using UV light in every step of the procedure. The hybrid multilayer films consisting of layers of zinc peroxide nanoparticles and hydrogel alternating in a sandwich-like fashion with thicknesses of 65–246 nm. The chemical structures of the hybrid films were investigated by FTIR spectroscopy, their morphology was studied by atomic force microscopy (AFM). The build up of the films was studied by measuring the optical reflection spectrum, and we have calculated the refractive index and layer thickness of the hybrid layers using simulating software. The adsorption properties of the ZnO2/hydrogel nanohybrid composite networks were investigated by measuring water and ethanol vapour adsorption by a quartz crystal microbalance (QCM). It was established that on partially hydrophobic ZnO2/PNIPAAm hybrids the adsorbed amounts were lower, against the hydrophilic ZnO2/PAAm film the vapour amount was higher. These results correspond to those of the bulk gel swelling results.

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    • "The development of humidity sensors based on QCM attracted the interest of a number of researchers and a range of surface components were investigated for the detection and quantification of water vapour. Examples of such surface components included porphyrins (Korposh et al., 2010), novel ruthenium polypyridyl complexes (Ocakoglu and Okur, 2010), sulfonated calix[4] arene (Okur et al., 2010a; Okur et al., 2010b), zinc peroxide in a hydrogel (ethanol vapours were also detected) (Sebok et al., 2010), nanofibrous polyacrylic acid/poly(vinyl alcohol) (Wang et al., 2010b), polyethylene imine/chitosan (Wang et al., 2010d), a sulfonated tetrafluoroethylene polymer (Nafion) (Wu et al., 2010b) and mesoporous silica (Zhu et al., 2010). Water vapour, as well as other polar molecule vapours, were assessed for binding to calcein thin films and QCM was used alongside surface plasmon resonance and visible spectroscopy to find that calcein films were highly sensitive compared to similar surfaces (Kruglenko et al., 2010). "
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