Abstract: A novel approach for preparing carbon-encapsulated nanomaterials is reported, in which apoferritin molecules, a kind of biomaterial with hollow cages, were used as the starting nano-sized reactors to trap the precursors of magnetic metals(Mn, Co). It has shown that the nano-sized metal particles can be effectively encapsulated inside the carbon shells that are formed by carbonizing protein molecules below 800 ℃ in a controllable way. The transmission electron microscopy images show that the as-prepared nanoparticles consist of a metal core and a carbon shell with narrow size distribution. The mechanisms of mineralization of apoferritin and carbonization of the mineralized protein are discussed in terms of the structure and properties of the protein precursor. It is believed that this novel approach may provide a new option for preparation of carbon-encapsulated nanomaterials based on other biomaterials such as fungi and actinomycete.

Key words: Fullerenes, Apoferritin, Mineralization, Carbonization, Carbon encapsulated 　nanomaterials