Solution-based doping of manganese into colloidal ZnO nanorods

This manuscript describes the low-temperature, solution-based doping of Mull ions into colloidal ZnO nanorods, and the yield of the products is in a gram scale. The structures and chemical compositions of the products were characterized by XRD, XPS, EDS, and FT-IR spectroscopy. The results demonstrate that Mn2+ ions were successfully incorporated into the lattice position of Zn2+ ions in ZnO. The concentration of Mn2+ ions (in molar %) in the products can be controlled in the range of 1.25 similar to 5%. The surfaces of Mn-doped ZnO nanocrystals have very rich hydroxyl groups, which enhance their solubility in many polar and nonpolar solvents. TEM and FESEM were used to characterize the morphology of ZnO and Mn-doped ZnO nanocrystals, and they revealed that both the undoped and doped ZnO nanocrystals are composed of uniform nanorods with a diameter of 8 nm and a length of 95 nm. The doping of Mn2+ ions has significant influences on the optical properties of ZnO nanorods. UV-vis absorption spectroscopy measurements reveal that the doping of Mn2+ lead to a red shift of the absorption edge of ZnO nanorods. Undoped ZnO nanorods exhibit a pure excitonic emission centered at 384 nm, whereas Mn-doped ZnO nanorods only show a red emission that is assigned to the Mn2+ T-4(G) ligand-field excited state.