holder

The following is an abstract for the selected article. A PDF download of the full text of this article is available here. Members may download full texts at no charge. Non-members may be charged a small fee for certain articles.


Micro-Raman Spectroscopy Study of Colloidal Crystal Films of PolystyreneGold Composites

Volume 61, Number 11 (Nov. 2007) Page 1202-1210

Djaoued, Y.; Badilescu, S.; Balaji, S.; Seirafianpour, N.; Hajiaboli, A.R.; Banan Sadeghian, R.; Braedley, K.; Brüning, R.; Kahrizi, M.; Truong, Vo-Van


Monolayers and multilayers of polystyrene (PS)-gold composite films prepared by two different deposition methods have been investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and confocal Raman microspectroscopy. The intensity of the 1001 cm−1 ring breathing mode of PS is used to evaluate the degree of ordering of monolayers and multilayers within a colloidal crystal. The depth profiling capability of confocal Raman microscopy is used to probe the regions inside the fractures in multilayered films. The intensity profile of the 1001 cm−1 peak revealed the presence of fractures of different shapes with some PS microspheres at the bottom of the fracture. A strong increase in the Raman intensity (by 103 times) has been observed when probing the regions where Au nanoparticles are concentrated in aggregates of different shapes. This enhancement is attributed to the surface plasmons generated by the periodic structure of the gold nanoparticles.