Silica-based fibers with axially aligned mesopores from chitin self-assembly and sol-gel chemistry

Polysaccharide nanorods (chitin, cellulose) can be used as colloidal templates to form silica-based mesoporous materials by combining self-assembly and sol-gel chemistry. Chitin are chosen here for their properties, facile preparation from natural resources, because of the complexing properties free amino groups at surface in view further functionalization. Electrospinning ethanolic co-suspensions, containing chitin pore templates, siloxane oligomers silica precursors polyvinylpyrrolidone (PVP) spinning polymer, allows forming mats hybrid organic-inorganic fibers with diameters 200–300 nm range. The relative proportions each component adjusted meet specific characteristics (e.g. micro-/mesoporosity ratio). After calcination, present an open porosity studied TEM N2 volumetry. Elongated mesopores (100–200 long, 2–4 wide) created individual monocrystals nanorods. They highly oriented along fibers' axes orientational order parameters P2 > 0.95 volume contents φchitin* ≥ 0.2. Additional microporosity is provided removal PVP. Complementary viscosity measurements on initial co-suspensions allow discussing interactions between colloids possible impact materials’ textures observed. introduction a monomeric Ti4+ precursor leads isolated tetrahedral Ti units, distributed calcined porous possibly close pores surface. In addition, preliminary investigations processing Zn xanthate ZnS carbonized nanoparticles Zn/S molar ratio 1.