Nanometer-sized nickel hollow spheres

Hollow nickel spheres of 50-60 nm diameter have different properties from bulk nickel. For example, the authors demonstrate that the spheres exhibit a long-range magnetic-ordering transition at 575 K and enhanced coercivity. The facile synthesis of such spheres by mild hydrothermal redox reaction of nickel dodecylsulfate with NaH2PO2 (see Figure) is described.