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Structural Incorporation of Sorbed Molybdate during Iron(II)-Induced Transformation of Ferrihydrite and Goethite under Advective Flow Conditions

“…Molybdenum K-edge XANES spectra (Figure ) obtained for solids from the Phase I ferrihydrite (Fh-X) and goethite (Gt-X) columns exhibited a pronounced pre-edge peak at 20006 eV, two broad shoulders at 20 023 and 20 055 eV, and one broad peak at 20 039 eV (Figure ). These features are consistent with XANES spectra for the MoO 4 2– sorption reference and with published spectra for MoO 4 tetrahedra adsorbed onto goethite and sodium molybdate . Corresponding XANES spectra for Phase II ferrihydrite (Fh-L, Fh-H) and goethite (Gt-L, Gt-H) samples exhibited a suppressed pre-edge feature at 20 006 eV, emergence of a broad peaks at ∼20 025 and 20 037 eV, and a relative decrease in the broad peak at 200 9 eV.…”

Smart anti-corrosion self-healing zinc metal-based molybdate functionalized-mesoporous-silica (MCM-41) nanocomposite coatings

“…Some authors have mentioned some formation mechanisms that might be possible for molybdate presentation on the zinc surfaces of coatings. Wharton et al49 have reported that by combining zinc cations and molybdate anions, zinc molybdenum oxide may form:…”

Molybdenum–phosphorus compounds based passivator to control corrosion of hot dip galvanized coated rebars exposed in simulated concrete pore solution

“…The mechanism of formation of passive film on zinc surface by molybdate anion is reported to be identical to hexavalent chromium ion [40]. It is suggested that zinc in acidic environments dissolves to form Zn ++ with an accompanying evolution of hydrogen.…”

“…Due to local increase in pH at the cathodic sites caused due to discharge of proton, a co-precipitation of hydrated zinc and molybdenum oxides may take place. Wharton et al [40] have suggested that zinc cations (Zn 2+ ) may combine with molybdate anions to form zinc molybdenum oxide:…”