Small-Angle X-ray Scattering Study of Au Nanoparticles Dispersed in the Ionic Liquids 1-Alkyl-3-methylimidazolium Tetrafluoroborate

Abstract

It was recently discovered that the sputter deposition of metal onto the surface of an ionic liquid generates nanoparticles in the liquid with no additional stabilizing agents. We performed small-angle X-ray scattering (SAXS) experiments to investigate the structure of Au nanoparticles synthesized by this method and to reveal the properties of the ionic liquid that affect the formation process. For a systematic study of these properties, we selected imidazolium-based ionic liquids with different alkyl chain lengths fixing the anion BF 4-. The Au concentration dependence for the formation of the nanoparticles was also studied. The SAXS results revealed that Au nanoparticles with 0.75-3.5 nm diameter were generated under the experimental conditions and that the particle size was relatively uniform for a fixed condition. The results demonstrated that the particle size depends on the type of ionic liquid and on the concentration if the ionic liquid is fixed. Integrating the experimental results, it was concluded that the surface tension and viscosity of the ionic liquid played important roles in conjunction with the Au concentration. It was interpreted that the surface tension influences the initial formation process of nanoparticles on the surface of an ionic liquid, and the viscosity affects the aggregation process during the dispersion of the Au particles from the surface into the liquid.

On the formation of anisotropic gold nanoparticles by sputtering onto a nitrile functionalised ionic liquid

“…S2, ESIw) as already observed earlier. 38,39 Therefore, these results indicate that the surface composition of the (BCN)MIÁN(Tf) 2 differs from the short alkyl chain ILs. Moreover, the surface configuration of the nitrile functionalised IL is probably comparable to the long alkyl chain ILs, with the nitrile groups pointing to the vacuum, as in Fig.…”

Preparation of Inorganic Materials Using Ionic Liquids

“…In this case, ionic liquid fragments Figure 13. View of Jilin ionothermal synthesis-1 (JIS-1) structure along [100] …”

Temperature-independent formation of Au nanoparticles in ionic liquids by arc plasma deposition

“…UV-vis spectra and SAXS patterns were obtained using sample cells with thicknesses of 0.05 and 0.3 mm, respectively, immediately after the preparation of the Au NPs without any pre-treatment for the measurements. The detailed procedures were described in our previous study [24,27]. Although there are large aggregates, there is no doubt that the shapes of the initial particles are spherical and their sizes are less than 5 nm in all ILs.…”