Uniform Magnetic Chains of Hollow Cobalt Mesospheres from One-Pot Synthesis and Their Assembly in Solution


  • This project was financially supported by the National Natural Science Foundation of China (Grant No. 20673009) and the Program for New Century Excellent Talents in University (NCET-04–0164) as well as by the Engineering Research Institute, Peking University (ERIPKU-204030). SY acknowledges the support from HKUST via the HIA program and from the Research Grants Council of Hong Kong.


Magnetic chains up to 10 μm in length formed of hollow cobalt mesospheres (480–850 nm) with a 60 nm thick shell are synthesized by a new soft-assembly protocol. The obtained chains show a saturation magnetization of 37.5 emu g–1, a remnant magnetization of 1.55 emu g–1, and a coercivity of ca. 66 Oe at 300 K. A possible mechanism for the formation of the chainlike hollow structures is proposed.