Soft, ternary, X- and gamma-ray shielding materials: paraffin-based iron-encapsulated carbon nanotube nanocomposites

Abstract

In the field of radiological protection, there is a growing interest in nano- and microcomposites due to their unique physicochemical properties, flexibility in the component selection (the base ingredient as well as the fillers), and lower toxicity in comparison to the lead (Pb)-based ones. In this study, we manufactured paraffin-based composites with different concentrations of iron-encapsulated multi-walled carbon nanotubes (Fe@MWCNTs) (10 and 20 wt%), which were prone to shape change at average room temperature. Long Fe@MWCNT arrays were synthesized by catalytic chemical vapor deposition (c-CVD) using a saturated (at 293.15 K) toluene solution of ferrocene (FeCp₂) (9.6 wt%) as a feedstock toward the highest efficiency for a complete Fe-encapsulation. The experimental data indicate that the shielding properties against gamma- and X-ray radiation are influenced by the filler concentration – the higher CNT content resulted in a greater ability to attenuate incident ionizing radiation. Finally, Fe@MWCNT–paraffin composites demonstrated corrosion resistance, as they did not react with 1 M aqueous solutions of NaCl, NaOH, and HCl.