INCORPORATION OF Mo6+ IN FERRIHYDRITE, GOETHITE, AND HEMATITE

Abstract Among all iron oxides, hematite (α-Fe 2 O 3 ), goethite (α-FeOOH), and ferrihydrite (FeOOH⋅ n H O) are the most common mineral species. While immobilization of Mo 6+ by surface adsorption on ferric oxides has been studied extensively, mechanisms incorporation in their structure have researched little. The objective this study was to investigate relation between content its structural hematite, goethite, six-line a combination X-ray absorption spectroscopy (XAS), powder diffraction (pXRD), inductively-coupled plasma optical emission spectrometry (ICP-OES). Synthesized presence Mo, phases incorporated up 8.52, 0.03, 17.49 wt. % respectively. For pXRD analyses did not indicate separate phases. Refined unit-cell parameters correlated with increasing concentration goethite. indicated an increase disorder within both and, therefore, supported Analysis measurements Mo-bearing ferrihydrites revealed small amounts coprecipitated akaganéite. near edge (XANES) at L -edge strong distortion MoO 6 octahedra three Fitting extended fine (EXAFS) spectra K such distorted coordination environment similar Fe position investigated specimen. Incorporation 3+ -position for resulted formation one vacancy close proximity newly charge balance structures.