Formation of lepidocrocite (gamma-FeOOH) from oxidation of nanoscale zero-valent iron (nZVI) in oxygenated water

To assess the aquatic reactivity, toxicity, fate and transport of materials, it is essential to determine their transformations in terms composition, morphology and surface characteristics in water. In work, oxidation products of nanoscale zero-valent iron (nZVI) characterized with spherical aberration corrected scanning mission electron microscopy (Cs-STEM) integrated with selected electron diffraction (SAED) and energy-dispersive X-ray (EDS). Crystalline structures from nZVI oxidation in oxygenated are identified. The results of Cs-STEM, EDS, X-ray diffraction ( Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) prove that the main products are oxyhydroxides (FeOOH), lepidocrocite (gamma-FeOOH).