Novel, ternary clay/polypyrrole/silver hybrid materials through in situ photopolymerization

Clay-polypyrrole-silver hybrid material was synthesized via one pot photopolymerization of pyrrole using silver nitrate as a photosensitizer in the presence of clay (montmorillonite, MMT). We have silanized the clay using a pyrrolyl-functionalized silane to provide anchor sites for the polypyrrole/silver composite coating (PPyAg). The silanized clay was effective in the making of a ternary hybrid material (MMT-Sil-PPyAg) which exhibits a PPyAg-rich surface. The polypyrrole and silver mass loadings were estimated to 19 and 27 wt.%, respectively. Interestingly, silanization by pyrrole functionalized silane permits to fully exfoliate the clay upon the photopolymerization process. In contrast, without silanization, the surface of the ternary hybrid material MMT-PPyAg is rather aluminosilicate-rich despite a black colour of the final product. We demonstrate that the anchored Ag particles are in the metallic state. We evaluated the propensity of the PPyAg-modified silanized clay to catalyse the reduction of methylene blue by NaBH4 and found it levels off to 94% within a few minutes only. This work conclusively demonstrate that UV-induced polymerization of pyrrole in the presence of a layered silicate is simple and fast; in addition, it permits to design novel hybrid materials with high catalytic performances (C) 2013 Elsevier B.V. All rights reserved.