Fabrication And Properties Of Clay Nanomaterials Derived From Natural Cellulose Substances

With the rapid development of the global economy and industry, large consumption of nonrenewable resources and environmental pollution problems have aroused people’s attention. In order to sovle these problems, newable resources and environment friendly materials need to be used instead of nonrenewable resources. Natural cellulose substance is the most abundant organic raw materials, which possesses biodegradability, good biocompatibility, nontoxicity and porosity, therefore natural cellulose materials can be used as a template to prepare advanced functional materials. Clay as a natural mineral material which has unique physical and chemical properties, has been applied in all aspects of life. The combination properties of cellulose and clay materials can be used to prepare clay modified celluose functional materials.Herein, we employed natural cellulose substance (ordinary quantitative filter paper) as template, directing the self-assembly of guest substances such as inorganic oxides, polymer chains, clay, resulting in a variety of advanced functional clay materials. The details are described as follows:(1) The fabrication of hierarchical nanotubular clay materials and the decoloration of aqueous methylene blue. Uniform ultrathin titania gel film was first deposited on cellulose nanofiber by means of a surface sol-gel process, followed by layer-by-layer self assembly of PDDA and clay nanosheets (kunipia-F) relying on electrostatic interaction. Therefore the clay modified cellulose material cellulose/titania/PDDA/kunipia-F was prepared. Zero-valent iron nanoparticles (Fe-NPs) were immobilized onto the as-prepared material via in-situ reduction, resulting in a composite material which has good efficiency of decoloration of aqueous methylene blue. The as-prepared material cellulose/titania/PDDA/kunipia-F/Fe NPs was calcined to remove cellulose and polymer and resulting in titania/kunipia-F/Fe2O3hybrid material, which inherited the sophisticated structures and hierarchical morphologies of the original cellulose substance.(2) The fabrication of hydrophobic material and heavy metal ion-trapping material based on natural cellulose. An ultrathin titania gel film was deposited on cellulose nanofiber by means of a surface sol-gel process, followed by layer-by-layer self assembly of PDDA and clay nanosheets (kunipia-F), then the composite material was modified with trimethoxy(octadecyl)silane(TMOS), the resulting functional material showed superhydrophobicity. Modification of N-[3-(Trimethoxysilyl)propyl] ethylenediamine onto cellulose/titania/PDDA/kunipia-F resulted heavy metal ion-trappping material. The composite material can be employed to adsorb Pb2+and Cu2+from aqueous solution. After calcination of the functional material which have adsorbed heavy metal ions, the metal oxide hybrid materials was obtained.(3) The fabrication of cytochrome c/titania/clay nanocomposite templated by natural cellulose substance. Cellulose/titania/PDDA/kunipia-F was fabricated by means of a surface sol-gel process and layer-by-layer self-assembly, then after calcination the cellulose and polymer components were removed, resulting in titania/kunipia-F nanotuber materials, in which kunipia-F has layered structure and was negative charged. Cytochrome c can be adsorped in the material and the cyclic voltammetry revealed the redox peaks of cytochrome c in Cyt c/titania/kunipia-F modified glassy carbon electrode with a three electrode electrochemical system. In1mM hydrogen peroxide solution, the modified GC Electrodes revealed improvement of reduction current of cytochrome c.