Calculation of parameters of elementary nanocrystals of liquid metals at melting temperature

Method of calculation and calculated values of parameters of elementary nanocrystals of liquid metals at melting temperature are given. It has been shown that radii of elementary nanocrystals are from 2 nm to 12 nm, and the number of atoms in each elementary nanocrystal varies from 2000 to 100000. This provides liquid metals with a high solidification rate and explains the abnormally high diffusion coefficient in liquid metals compared to solid metals.

High Diffusivity Coefficient of Cyclic Voltammetric Behaviour of Semicarbazones and Thiosemicarbazones and their Antimicrobial Studies

In this work, a series of N-hydroxy-2,6-diaryl-3-alkylpiperidin-4-one semicarbazones and thiosemicarbazones have been synthesized and also subjected towards cyclic voltammetric studies. The structure of reduced products was confirmed by FTIR, 1H & 13C NMR spectral analysis. Further products were also screened for antimicrobial activities and it shows high significant effect towards Aspergillus niger among the eight tested fungal species. The propency towards order of reduced products is observed sharply and it was established that irreversible reduction of two electron transfers has taken for all four synthesized compounds and highly pH dependent. Among the synthesized compound, thiosemicarbzones showed versatile features with high diffusion coefficient value in minimum power consumption of current function.

Electrochemical detection of SO2 in a hydroxyl functionalized and eutectic-based ionic liquid

Using ionic liquids (ILs) as electrolytes in developing electrochemical sensors for SO2 detection is of much interest. We compared the electrochemical behaviors of SO2 in choline chloride–ethylene glycol-based deep eutectic solvent (ChCl–EG-based DES), 1-(3-hydroxypropyl)-3-methylimidazolium tetrafluoroboride ([C3OHmim]BF4), and [C3OHmim][Formula: see text]monoethanolamine (MEA) (6.2:1 in molar ratio). Addition of MEA into [C3OHmim]BF4 can significantly increase the SO2 absorption capacity and enhance the electrochemical response of SO2. However, as we use ChCl–EG-based DES, the reduction current is 10 times larger than in [C3OHmim]BF4 and 4 times larger than in [C3OHmim][Formula: see text]MEA (6.2:1 in molar ratio). And SO2 gas shows high diffusion coefficient value as in the ChCl–EG-based DES. A good linear relationship between the reduction current and the SO2 content was obtained in the tested SO2 gas content range from 200[Formula: see text]ppm to 1500[Formula: see text]ppm. Our findings provide new route for DESs as electrolytes for SO2 sensor designing with high sensitivity.

Influence of Roasting Temperature on Electrochemical Performance of LiNi0.5Mn1.5O4 Cathode for Lithium-Ion Battery

Nanomicro spheres of LiNi0.5Mn1.5O4 materials are prepared by carbonate coprecipitation method. The effect of calcination temperatures on morphology and electrochemical property is explored. Results show that the structure of the material becomes more compact with the increase of the temperature, which is propitious to the improvement of electrical conductivity and activation level of the material. The charge–discharge tests show that the sample obtained at 850 °C (LNMO850) exhibits optimal rate capability and cyclic stability, due to the fact that LNMO850 has a high diffusion coefficient, which is propitious to the improvement of electrical conductivity and activation level of the material.

Synthesis and Electrochromic Properties of Crystalline 3D Urchin-Like Nanostructures

Novel 3D (three-dimensional) urchin-like WO2.72nanostructures were prepared by a template-free hydrothermal synthetic route using W(CO)6and ethyl alcohol reagents. The detailed morphology and crystallinity were dependant on the synthesis temperature and synthesis time. The potential use of WO2.72nanourchins as a cathode electrode for electrochromic devices was assessed. The WO2.72electrochromic films exhibited a rapid switching response time (coloring time ~5 s, bleaching time ~1.6 s), outstanding high coloration efficiency (~116 cm2/C), and durability in an acidic electrolyte. This performance was attributed to the high diffusion coefficient [~6.43×10-9 cm2/s (in the intercalation)] of the urchin-likeWO2.72with a high surface area to volume ratio and high crystallinity

Preparation and Characterization of Bismuth Molybdate Catalyst for Oxidative Dehydrogenation of n-Butene into 1,3-Butadiene

α-Bi2Mo3O12 and γ-Bi2MoO6 catalysts were prepared by co-precipitation method, and they were applied to the oxidative dehydrogenation of n-butene into 1,3-butadiene in a continuous flow fixed-bed reactor. Formation of α-Bi2Mo3O12 and γ-Bi2MoO6 catalysts was well confirmed by XRD, Raman spectroscopy, and ICP-AES analyses. The γ-Bi2MoO6 catalyst exhibited a better catalytic performance than the α-Bi2Mo3O12 catalyst. Catalytic performance of γ-Bi2MoO6 strongly depended on the pH value used in the co-precipitation step. It was also revealed that a mixed catalyst comprising γ-Bi2MoO6 (90 wt%) and small amount of α-Bi2Mo3O12 (10 wt%) showed the best catalytic performance due to the synergy effect of two components. It is believed that the high catalytic performance of the mixed catalyst resulted from high diffusion coefficient of lattice oxygen in the γ-Bi2MoO6 and from abundant chemisorption sites for n-butene in the α-Bi2Mo3O12.

Synthesis and characterization of Pd nano-pillar arrays in the metal hydride switchable mirror

A method is suggested for improving the switching characteristics of the metal-hydride mirror by enhancing hydrogen transport in the active film. Nano-pillars of palladium, which has a high diffusion coefficient for hydrogen, are introduced into the active layer and should serve as a “highway” for the rapid introduction of hydrogen. A palladium nano-pillar array is made by electrodeposition in the pores of a polycarbonate membrane. The membrane is dissolved and the active layer (an yttrium-magnesium alloy) is evaporated on the palladium nanostructures. Improved kinetics has not been shown conclusively and is still the subject of research.

Properties of RF Sputtered ZnTe:N films for Back Contact to CdS/CdTe Solar Cells

ABSTRACTMost of the low resistance back contacts formed on high efficiency CdS/CdTe solar cells involve copper either in elemental form (such as Cu/Au back contacts) or as dopant in other material (such as Cu-doped ZnTe). But copper is also suspected to be a cause of degradation of devices in long-term stability tests due to its high diffusion coefficient in polycrystalline CdTe. In this paper, we present results on the development of nitrogen-doped ZnTe back contacts for CdS/CdTe solar cells. Reproducible N-doped p-ZnTe films were prepared using reactive RF magnetron sputtering with Ar/N2 gas mixtures. The conductivity of the doped ZnTe films was more than five orders of magnitude higher than that of intrinsic films. We find that annealing in air can further increase the conductivity. Efficiencies near 10% have been achieved with a ZnTe:N/Ni back contact.