Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr0.53Ti0.47O3) (1-x)- (PbFe0.5Ta0.5O3)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm2, which actually increases (to 40 μC/cm2) in the high-T tetragonal phase, representing an exciting new room temperature oxide multiferroic to compete with BiFeO3. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature multiferroics known, which is a great advantage for magnetoelectric devices

Monodisperse hollow magnetite microspheres were successfully synthesized by an one-step process through a tem-plate-free hydrothermal approach employing simultaneously a mixture of FeCl₃.6H₂O and ferrocene as precursor and a propylene glycol-isopropanol mixture as solvent. The morphologies and properties of the magnetite microspheres were characterized by X-ray diffraction (XRD), Raman and infrared spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), adsorption of nitrogen (BET method) and SQUID magnetometry. The results show that the microspheres consist of a single crystalline phase of magnetite. On the other hand, the size and the internal hollow of the microspheres depend on the temperature of growth and can be tuned by modifying the synthesis conditions

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A thorough structural characterization of the synthesized Ni-, Zn-, and Cd-nitroprussides (NPs) with X-ray diffraction (XRD), thermogravimetric analysis, diffuse reflectance infrared Fourier transform spectrometry (DRIFTS), M€ ossbauer spectroscopy, and magnetic measurements was performed. However, the innovative part of the research was the study of the structural effects and the interactions of the CO 2 molecule with the Ni-, Zn-, Cd-NP frameworks. DRIFTS of adsorbed molecules, high pressure adsorption, and in situ XRD adsorption experiments were performed. The DRIFTS spectra displayed peaks assigned to CO 2 physical adsorption and the formation of adducts (M 2+ 3 3 3 OdCdO). The fitting of the adsorption data to the DubininÀRadushkevich equation and a Langmuir-type equation for volume filling allowed the calculation of the micropore volume and the isosteric heats of adsorption. The calculated parameters indicated an unusual behavior of the adsorption process in Cd-NP at high pressure. This fact was caused by the interaction of CO 2 molecules with the framework cations and the small adsorption space of Cd-NP. The Ni-and Zn-NPs behaved normally. The Pawley fitting of the XRD profiles of the dehydrated materials and under CO 2 adsorption indicated that in both cases Ni-NP, Zn-NP, and Cd-NPs displayed the Fm3m, R3, and Pnma space groups, respectively. The dehydrated samples demonstrated a change in the cell parameters. However, only Cd-NP presented a noticeable variation of its cell parameters under CO 2 adsorption. This fact was linked to the unusual behavior of the adsorption process in Cd-NP. Additionally, was shown that dehydrated Ni-, Zn-, and Cd-NPs can store 27, 22, and 15 wt % of CO 2 at 298 K and 9 atm., respectively. Then, Ni-and Cd-NPs are excellent for CO 2 storage, and Cd-NP is good for gas cleaning.

Platinum was electrodeposited onto Y-zeolite and Y-zeolite (Y)/Vulcan XC-72R (V) to produce Pt/Y/V and Pt/Y catalysts using a rotating disk slurry electrode technique. The activities of the two catalysts were measured towards methanol electro-oxidation in alkaline media by cyclic voltammetry and chronoamperometry. The materials were examined using electron microscopy. The results were compared to those obtained on commercial catalysts. Pt/Y/V (with 14 wt% Pt) catalyst was the most active, even more so than a commercial Pt/V catalyst with 20 wt% Pt. The Pt/Y/V catalysts contained Pt nanoparticles and tetrahedra, likely a consequence of the nucleation and growth within the zeolite framework.