Hierarchical nanotubular clay materials derived from natural cellulose substance

Versatile hierarchical nanotubular clay materials were fabricated by using natural cellulose substance as template. Cellulose nanofibers were pre-coated with ultrathin titania gel films employing the surface sol–gel process, followed by layer-by-layer self-assembly of poly(diallyldimethylammonium chloride) and the specific clay nanosheets (kunipia-F, montmorillonite-K10 and sumecton-SA) through electrostatic interactions. The as-deposited cellulose/titania/polymer/clay composite sheets were calcined to remove the organic components, resulting in bulk hierarchical nanotubular titania/clay hybrid materials. Further sulfuric acid solution treatment of the resultant titania/kunipia-F hybrid sheet led to the pure nanotubular structured kunipia-F material. Low-temperature sodium hydroxide/urea solution treatment of the as-prepared cellulose/titania/polymer/kunipia-F composite sheet formed nanotubular titania/polymer/kunipia-F hybrid. Iron nanoparticles were immobilized onto the as-prepared cellulose/titania/polymer/kunipia-F composite sheet as the substrate, resulting in a new composite material showing high efficiency of decoloration of aqueous methylene blue.