Bacteria-mediated synthesis of free-standing cobalt oxide rods.
We demonstrate the simple room-temperature preparation of rod-type, oxide nanostructures derived from the Bacillus subtilis templates. Specifically, free-standing, cobalt oxide rods were produced via the following systematic processes: incubation of the bacteria templates in aqueous cobalt chloride solution, reduction with sodium borohydride (NaBH4), and subsequent oxidation in water at room temperature. We observed that single nanocrystals or small clusters approximately 3 to 5 nm in diameter were uniformly distributed on the as-prepared individual rods. Additionally, thermogravimetric (TG) analysis and field emission electron scanning microscopy (FESEM) observation revealed the important role played by the concentration of the reductant, NaBH4, in anchoring the cobalt oxide nanocrystals on the bacterial cell surface. Our proposed strategy facilitates the economic and easy construction of other oxide nanostructures and assemblies for applications in nanoelectronics, photonics, sensing, catalysis, and energy storages.
Shim
Hyun-Woo
HW
Department of Materials Science and Engineering, College of Engineering, Ajou University, Suwon 443-749, Korea.
Lee
Chang-Soo
CS
Kim
Dong-Wan
DW
D001412:Bacillus subtilis / Q000378:metabolism*; D003035:Cobalt; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes; D010087:Oxides / Q000138:chemical synthesis*; D055672:Static Electricity
D010087:Oxides; D003035:Cobalt; C060728:cobalt oxide