Solid-state phase transformations in solution: templated conversion of nanoscale nickel phosphides.

Conversion of Ni(12)P(5) nanoparticles to Ni(2)P is demonstrated to occur via a solid-state, rather than a solution dissolution, process. The templated transformation is employed to make monodisperse hollow or solid particles of the catalytically active phase Ni(2)P with surface areas of ~17 m(2) g(-1).