Smart Materials & Structures

Biological systems found in nature provide excellent examples of highly controlled and organized architectures that generate complex materials. Using these materials and their unique microstructures as templates to produce nano-structured materials can result in some special results that manmade templates can rarely/can’t achieve at current time.Th is presentation will demonstrate an innovative technology to produce the copper-carbon-core-shell nanoparticles (CCCSNs) using cellulose as templates (US Patent No.: US8,828,485 B2). Th e technology relies on reducing the Cu+2 ions by absorbing them in the cellulose (C6H10O5)n structures of natural fi bers and then, going through carbonization and refi ning processes to produce the CCCSNs. In contrast to the conventional methods, the nanoparticles made from this technology are core/shell structures in nature and dispersible in both water and organic solvents (such as oil) with very low cost. CCCSNs possesses many special properties that commercially available copper nanoparticles couldn’t have. CCCSNs have high physical/chemical stabilities and form the Cu<=>Cu2O equilibrium system without forming cupric oxide, which is signifi cant since cuprous oxide is an optical catalyst material with relatively low bandgap (2.137eV).Th e most unique property is the regeneration behavior of CCCSNs, when treated with reducing environment, the Cu<=>Cu2O system will return to pure copper status with no signifi cant changes in particle size distribution or core-shell structure. Because of the excellent stability, superior performance and low cost, CCCSNs have been tested as anti-bacteria; anti-termite; anti-algea and as an optical catalyst for volatile organic compounds (VOC) treatment reagents and achieved outstanding results.