All change for nanocrystals

Until recently, to prepare nanocrystals of a new material, scientists searched their shelves for the appropriate molecular precursors, surfactants, and solvents. They then optimized the reaction conditions for the atoms to self-assemble into monodisperse nanocrystals (1). This approach is being replaced by a simpler strategy, in which preformed nanocrystals serve as templates to produce nanoparticles with a different composition through chemical transformation. On page 964 of this issue, Oh et al. (2) report a powerful mechanism that allows the composition of oxide nanoparticles to be transformed in solution and at low temperatures.