CELL 100 |
| Cellulose nanocrystal (CNXL), which is separated from cotton cellulose by acid hydrolysis, has been utilized for the synthesis of various kinds of metal and metal oxides. The surface hydroxyl groups serve to reduce metal ions such as Ag(I), Pt(IV), Pd(II), and Se(IV) to corresponding nanocrystalline metals at 160-200oC in air without adding any reducing agents. The original crystalline structure of the CNXL is maintained in the temperature range and the hydroxyl groups reduce metal ions to metal nanocrystals on the CNXL surface. For the reduction of early transition transition metals including Ni(II) and Cu(II), higher thermal treatment is required under N2 due to their high oxidation potential. Metal particle sizes can be controlled by controlling amount of metal ion loading and surface hydroxyl groups prevent aggregation of nanocrystalline metals. When large amount of Pt(IV) was loaded, Pt nanorods were aligned through the molecular tracks of surface hydroxyl groups. We will also discuss preliminary results on catalytic activity of Pd/CNXL composites for Heck reaction and UV-initiated decolorization of methylene blue on Se/CNXL. |
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Nanotechnology: A Fiber Perspective
8:30 AM-11:00 AM, Monday, March 26, 2007 McCormick Place Lakeside -- Room E352, Level 3, Oral
Division of Cellulose & Renewable Materials |