Jan 26, 2009
Stable Ag/carbon composite displays strong antibacterial properties
Carbon-based composites are of great importance due to their unique structures, novel physical and chemical properties, and potential applications in many areas. However, carbon-based composites are often obtained by complicated multi-step processes including first preparation of carbon particles, surface modification followed by combination of them with functional materials. The dispersion size can be difficult to control for the particles dispersed on the carbon carrier. In addition, the carbon sources in most synthesis routes are expensive or toxic resources. Therefore, a simple strategy for preparing carbon and carbon-based composites from readily available resources will undoubtedly benefit their further applications.
Honggang Fu and co-workers from Heilongjiang University, China, have come up with a straightforward approach for preparing Ag/Carbon composites based on the coordination interaction of the carbon source and the metal precursor. The acrylic acid type resin CD-180, a polymer processing abundant tunnels with exchangeable sodium ions, was selected as carbon source. The Ag/Carbon composites, where the Ag nanoparticles were well dispersed on the surface of carbon with tuned size, were obtained by exchange of sodium ions with silver ions to obtain resin-Ag+ composites followed by carbonization of them at certain temperature. The antibacterial assay showed that the composites possess high stability and good antibacterial properties that are determined largely by the Ag particle size.
In the strategy, the carbon precursor with different functionality can be selected, such as the glucose and starch with abundant hydroxyl, other ions-exchange resin with amido or carboxyl group, and castoff from farm produce that contains a plenty of cellulose. Based on the coordination interaction, different metal ions (Fe, Co, Ni, Ag, Au, Zn, Pd, W, Mo etc) can combine with the carbon precursor, and consequently, the carbon with different crystalline and carbon-based composites with different component can be prepared, including graphic carbon (GC) capsule, nanosheet, Ag/GC composites, WC/GC, MoC/GC and ZnO/GC etc. These materials are of promising in adsorption and separation, medicine, catalysis and optical-electric conversion areas.
About the author
Prof. Honggang Fu is based at the Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin, China.