Inorganic Chemistry in a Nanoreactor: Doped ZnO Nanostructures by Miniemulsion

Doped M:ZnO nanoparticles (Zn/M = 50:1 or 20:1; M = AgI, CoII, CuII, EuIII, MgII, MnII) have been produced by an easy, reproducible, and fast inverse miniemulsion approach, enabling the co‐precipitation of the nanocrystalline oxide in a confined space. Unexpectedly, the formation of crystalline materials took place at room temperature. Suspensions were characterized by dynamic light scattering and UV/Vis spectroscopy, whereas precipitated powders were characterized by X‐ray photoelectron spectroscopy, X‐ray diffraction, transmission electron microscopy, inductively coupled plasma atomic emission spectrometry, and thermogravimetric analysis. The particles obtained showed preferential growth along the [0002] direction with a size of 70 nm, whereas along the other directions average sizes of between 26 and 33 nm were determined. The analyses confirmed successful doping in all cases but one: In fact, the Ag‐doped sample is a nanocomposite consisting of metallic silver clusters dispersed in the ZnO matrix. Red emission from the ZnO:Eu sample was evidenced upon excitation at around 465 nm. Doped M:ZnO nanoparticles (Zn/M = 50:1 or 20:1; M = AgI, CoII, CuII, EuIII, MgII, MnII) have been produced by an easy, reproducible, and fast inverse miniemulsion approach, enabling the co‐precipitation of the nanocrystalline oxide at room temperature in a confined space and achieving good particle size control.