A deep look into the diverse surface speciation of the mono-molybdate/lepidocrocite system by ATR-IR and polarized ATR-IR spectroscopy

The present study is focused on the adsorption of monomeric molybdate anions surface lepidocrocite investigated by several infrared spectroscopy methods. To speciation molybdates lepidocrocite, behavior anion at interface upon increasing concentration (fixed pH) or decreasing pH concentration) was analyzed in situ. obtained results expand knowledge for revealing a second complex, which more stable, arising from interaction with defects (010) facets lepidocrocite. A curve fitting procedure enabled us to confirm what observed pristine spectra, and outer-sphere complexes were probed as well. evolution different bands adsorbate pH, fitting, shows complex species protonation, formation strongly bonded low pH. 2D synchronous asynchronous spectra support interpretation data. Furthermore, insights into orientation respect are using linearly polarized radiation. most conclusions ascertained basis unpolarized spectra. combination methodologies yields consistent picture complexity this system paves way subsequent utilization approach other systems.