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Nano-boehmites with a range of controlled sizes and morphologies exhibiting high dispersability in water were synthesized through a free-additive hydrothermal methodology.

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The range of compositions and temperatures at which single-phase tetragonal and monoclinic Fe-containing zirconia nanoparticles are stable is reported. Both types of iron-doped zirconia particles were synthesized by annealing dried gels FexZr1-xO2, with nominal compositions in the range 0 ≤ x ≤ 0.15, over the range of temperatures between 400 °C and 1300 °C. Monophasic crystalline specimens of Fe-ZrO2 solid solutions were characterized by different techniques including X-ray powder diffraction (XRD), infrared and Raman spectroscopies (IR and Raman), and transmission electron microscopy (TEM). Energy gaps were estimated from diffuse reflectance ultraviolet-visible spectra (DRUV-Vis) and compared with those obtained from electrochemical data. Upon increasing the amount of iron in both types of iron-containing zirconia-based structures the energy gaps slightly lowered. The electrochemical properties of those solid solutions obtained using the voltammetry of microparticles (VPM) technique indicated the presence of a small portion of iron as Fe(2+) in both types of crystalline Fe-doped ZrO2. Electrochemical data suggest that the monoclinic solid solutions provide a particularly high accessibility for promoting catalytic processes such as electrochemical oxygen reduction.

The use of Raman spectroscopy for discriminating monetary emissions, a recurrent problem in much archaeological studies, is described. The method involves the record of Raman signatures of tenorite and crystalline and defective cuprite in the patina based on the idea that subtle, mint‐characteristic variations in the composition and metallography of the base metal during the manufacturing process are reflected in the variation in depth of the composition and crystallinity of the corrosion patina. The technique was applied to a series of 10‐cash copper coins produced around the transition between the Kuang Hsü and Hsüan T'ung last Chinese emperors and the first Republic whose averaged composition was 95 ± 1% wt Cu plus 5 ± 1% wt Zn often accompanied by traces of Sn and Pb. Raman data, corroborated by focusing ion beam‐field emission scanning electron microscopy and voltammetry of immobilized particles measurements, suggested the possibility of discerning between different provincial and regular unified currency productions.