Solution route to single crystalline dendritic cobalt nanostructures coated with carbon shells

Abstract

Single crystalline dendritic cobalt was coated with carbon by an easy two-step solution route with glucose as carbon source. The characterization and magnetic properties of carbon-coated cobalt nanostructures were investigated. The thickness of the carbon shell was well controlled in the range 100–250 nm by varying the mass ratio of the metal particles to glucose. The as-prepared cobalt/carbon core–shell nanostructures exhibit good stability in concentrated HCl (37 wt%) solution. The saturation magnetization of cobalt in the core–shell nanostructures at room temperature is similar to the bulk ferromagnetic element counterpart but is higher than that of the original single crystalline dendritic cobalt. The surfaces of cobalt/carbon core–shell nanostructures, abundant in organic functional group such as –OH and –COOH, could be loaded with bio-molecule such as ibuprofen easily, which may be used in clinic diagnostics, molecular biology, bioengineering, and catalysis by loading with other functional molecules (e.g. enzymes and antigens).