Iron Oxyhydroxide Aerogels and Xerogels by Hydrolysis of FeCl₃ ∙ 6 H₂O in Organic Media: Early Stages

Abstract

Formation of iron oxyhydroxide aerogel and xerogel by hydrolysis of FeCl3 ∙ 6 H2O was studied in organic media using water available solely from the starting iron salt. Ethylene glycol (EGLY), dimethyl sulfoxide (DMSO) and dimethyl formamide (DMFA) solvents were used. Products were analysed with specific surface area and TEM measurements. Early stages of hydrolysis and progress of gelation were followed by Mössbauer spectroscopy of frozen reaction mixtures. Presence of transient species and increase of the probability of the Mössbauer effect was observed in the early phase (0 – 60 min). Hydrolysis and gelation were the faster in EGLY, proceeded with medium rate in DMSO and were the slowest in DMFA.