New polyoxometalate-functionalized cellulosic fibre/silica hybrids for environmental applications

• Autor(a) principal: Gamelas, J. A. F.
• Data de Publicação: 2012
• Outros Autores: Evtyugina, M. G., Portugal, I., Evtuguin, D. V.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/26978

Cellulosic fibre/silica hybrid materials functionalized with Keggin-type polyoxometalates ([PV2Mo10O40]52, [PVMo11O40]42, ([PMo12O40]32 or [PW12O40]32) were prepared by a sol–gel method at room temperature. The novel materials are composed of ca. 56 wt% of polysaccharides, ca. 37 wt% of propylamine-modified silica, 2 wt% of polyoxometalate, and 5% of hydration water. The silica network of these hybrids exhibits relatively high degree of condensation being distributed mainly on the surface of the cellulosic fibres as a dense film. The functionalization of silica with polyoxometalates via electrostatic interactions with protonated propylamino groups of modified silica was unambiguously confirmed. Despite their high silica content cellulose/silica hybrids retained basic cellulosic pulp properties—supramolecular and fibrous structure, porosity, relatively low density, etc. The novel bio-based material functionalized with 2% of [PVMo11O40]42 shows particularly high activity towards the oxidation of volatile organic compounds (VOCs) present in urban air thus anticipating future environmental applications.