UV-vis and Infrared Spectroscopic Investigation of Feroxyhite Nanomaterial Synthesis by AC Atmospheric Microplasma

Feroxyhite nanomaterials were synthesized in aqueous solutions by AC atmospheric microplasma at room temperature. The synthesized nanomaterials were characterized by X-ray powder diffraction, Raman scattering, and electron microscopy. The chemical reaction during the plasma synthesis was in situ and ex situ investigated by UV-vis spectroscopy and infrared spectroscopy. The initiation phase of the nanomaterial was detected from UV-vis absorption and infrared bands of hydroxyl radical. The synthesis-time-dependent crystallographic quality was detected from the bandgap of the nanomaterials, which was calculated with the Tauc method from the UV-vis spectra. The effects of voltage and electric strength were investigated too. The mechanism of the plasma synthesis was discussed.