Nanotechnology of colloids of metal nanoparticles using ionic liquids

Investigators: A. Cigáň, A. Dvurečenskij, M. Škrátek, M. Majerová, J. Maňka

Ionic liquids – liquids composed only of ions, have unique physicochemical properties, such as high thermal and chemical stability, the ability to dissolve various substances and negligible vapor pressure. These properties presuppose their use for the development of new technologies for the production of metal nanoparticles or their colloids for industrial and biomedical applications. Our attention was focused on the preparation and characterization of colloids of Ni and NiFe nanoparticles by magnetron sputtering directly on the surface of two ionic liquids [BMIM]. [PF6] and [BMIM]. [Tf2N] at room temperature. Detailed results of the study of the magnetic properties of the prepared colloids of Ni and NiFe nanoparticles during their storage for 34 months allow a better understanding of the interactions between ionic liquids and nanoparticles, as well as their theoretical modeling. The obtained results suggest a new way of preparing stable magnetic fluids. Nanoparticles with dimensions of Ni∼10 nm and NiFe ∼12 nm were stable for more than 2 years without signs of agglomeration and their sedimentation. The ionic liquid itself protects the nanoparticles from degradation. The nanoparticles show a superparamagnetic character with a blocking temperature of about 2.5 K.

Related projects:

  • VEGA 2/0164/17
  • VEGA 2/0149/17
  • APVV-16-0263
  • projekt ŠF EU 26240120019 (CENTE II)

Fig. 1 Paramagnetic component of FC molar magnetic susceptibility χe versus T colloid of Ni nanoparticles in ionic liquid [BMIM.Tf2N] before (triangle) and after 32 months aging (diamond) at 20 Oe and at magnetic field 2 kOe (square). The inset graph shows the corresponding ZFC characteristic of said nanocolloid.

 

The result was achieved in cooperation with the Institute of Electrical Engineering of the Slovak Academy of Sciences, the Center for Energy Research, the Hungarian Academy of Sciences and the Institute of Polymers of the Slovak Academy of Sciences.

 

Publication:

  1. CIGÁŇ, Alexander – LOBOTKA, P. – DVUREČENSKIJ, Andrej – ŠKRÁTEK, Martin – RADNÓCZI, G. – MAJEROVÁ, Melinda – CZIGÁNY, Z. – MAŇKA, Ján – VÁVRA, I. – MIČUŠÍK, M. Characterization and magnetic properties of nickel and nickel-iron nanoparticle colloidal suspensions in imidazolium-based ionic liquids prepared by magnetron sputtering. In Journal of Alloys and Compounds, 2018, vol. 768, p. 625-634. ISSN 0925-8388. (3.779-IF2017).