On the Synthesis of Molybdenum Nanoparticles under Reducing Conditions in Ionic Liquids

We report on attempts to synthesize Mo nanoparticles under reducing conditions in ionic liquids (ILs). Ionic liquids were based on the 1-ethyl-3-methylimidazolium or 1-butyl-3-methylimidazolium (Emim and Bmim, resp.) cations and the dicyanamide N(CN)2, triflate (OTf), bis(trifluoromethylsulfonyl)imide-(NTf2), tetrafluoroborate (BF4), ethyl sulfate (ES), and methylsulfonate (MS) anions. (NH4)6Mo7O24∗4H2O and NaBH4 were reacted in a set of imidazolium ionic liquids (ILs) at 180°C to evaluate the potential of the ILs for stabilization of metallic Mo nanoparticles. XRD and TEM reveal a strong influence of the IL anion on the particle sizes, shapes, and crystal structures. The influence of the IL cation and the reaction temperature is much less pronounced.