The effect of microtube formation with walls, containing Fe3O4 nanoparticles, via gassolution interface technique by hydrolysis of the FeCl2 and FeCl3 mixed solution with gaseous ammonia

Abstract

In this work, microtubes with walls, containing Fe 3 O 4 nanoparticles, obtained by "rolling up" of the interfacial films, were synthesized by the gas-solution interface technique (GSIT), using a mixture of aqueous solutions of FeCl 2 and FeCl 3 and gaseous ammonia. The synthesized microtubes were characterized by Scanning Electronic Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), X-Ray Diffraction analysis (XRD) and magnetization measurements. It was established that under optimal synthetic conditions the microtube diameter ranged from 5 to 10 µm, the length was up to 120 µm and the thickness of walls was about 0.6 µm, the walls themselves being formed by nanoparticles with a size of about 10 nm. The reversible hysteresis behavior, the low coercive force, the low remanence magnetization and the approaching of Mr/Ms to zero, confirmed the superparamagnetic nature of the synthesized microtubes. A hypothesis on the formation of microtubes by the gas-solution interface technique was proposed.