Vanadium oxide intercalated with polyelectrolytes: Novel layered hybrids with anion exchange properties

Abstract

Novel anion exchange hybrid materials were developed by the insertion of poly(diallymethylammonium chloride) (PDDACl) and poly(allylamine hydrochloride) (PAHCl) polyelectrolytes into V 2O 5 interlayer spaces using hydrothermal treatment and were used to host an anionic cyanine dye. A systematic study of the hybrid material synthesis by direct in situ reaction of PDDACl and PAHCl polycations with V 2O 5 powders showed that the interlayer space of V 2O 5 expands from 0.44nm to 1.40nm and 1.80nm upon intercalation of PDDACl and PAHCl polyelectrolytes, respectively. X-ray photoelectron spectroscopy and DR UV-Vis-NIR spectroscopy revealed that some V 5+ sites were reduced to V 4+ during the intercalation of the polyelectrolytes, these acted as both charge balancing entities for the negative oxide sheets and carriers for exchange sites located in the V 2O 5 interlayer space. The interlayer separation is consistent with the existence of coiled conformation of the polycations. The hybrid materials produced [PDDACl] 0.24[PDDA] 0.29V 2O 5 and [PAHCl] 0.28[PAH] 0.47V 2O 5, exhibited approximately 45.0% and 37.0% of chloride ions still available for anionic exchange, respectively. These materials were used to encapsulate a cyanine anionic dye. The presence of the dye was evidenced in the [PDDACl] 0.24[PDDA] 0.29V 2O 5 by significant fluorescence, with emission peak centered at 617nm. © 2011 Elsevier Ltd.