Liquid Gallium based temperature sensitive functional fluid dispersing chemically synthesized FeMB nanoparticles

Abstract

In this work, FeMB (M = Nb, V) nanoparticles were first reported to be synthesized by a chemical method, from reduction of FeCl2, NbF5 (and NH4VO3) using NaBH4 as a reducing agent in aqueous solution. A new temperature sensitive functional fluid was then prepared by dispersing silica coated FeNbVB nanoparticles in liquid gallium. The result shows that the FeNbVB nanoparticles exhibit an oxidation resistance better than that of FeNbB nanoparticles. The FeNbVB nanoparticles were in the size range of 30 – 50 nm and the thickness of silica layer was observed about 10 nm by means of transmission electron microscopy. The magnetization of the synthesized particles and fluid shows a temperature dependency within the testing temperature range of 293 – 353 K, which indicated their application potential in magneto-caloric energy conversion devices.