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MnO@multi-walled CNTs (MnO@MWCNTs) composite film electrodes with porous structure are synthesized by the improved electrostatic spray deposition (ESD) setup. The content of 5.47 wt% MWCNTs is found to be optimal, which can improve the conductivities of MnO film electrodes without destroying their porous structure and obtain good cycling performance (588 mAh g −1 after 100 cycles at 1 C) and high rate capabilities (424 mAh g −1 at 5 C). The effects of MWCNTs on the morphology of the electrodes and the electrochemical performances have been studied. It is found that the electrostatic repulsion between the charged spray droplets can be remarkably reduced by excessive adding MWCNTs, which leads to the breakdown of the 3D porous morphology of the MnO film electrodes and the electrochemical performance becomes worse. [ABSTRACT FROM AUTHOR]

Abstract The FeVO 4 nanoparticles are synthesized by a new and facile electrostatic spray assisted coprecipitation method. The effects of calcination temperature and crystal structure on electrochemical properties are discussed. X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption isotherms and galvanostatic cell cycling are used to characterize the structure and electrochemical performance of the FeVO 4 nanoparticles. Compare to the crystalline FeVO 4 , the amorphous contemporary prepared by a low-temperature thermal treatment exhibits an outstanding electrochemical performance, which deliver a high initial coulombic efficiency of 80.4%, stable cycling performance with a reversible capacity of 115.6 mAh g−1 after 100 cycles and high rate capacity of 89.7 mAh g−1 at 800 mA g−1. Highlights • The amorphous and crystalline FeVO 4 are prepared by a new ESAC method. • The amorphous FeVO 4 can be as a cathode for sodium-ion batteries. • The amorphous FeVO 4 shows excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract DyScO 3 single crystals were grown by the Czochralski method, and the magnetic properties and anisotropic magnetocaloric effect (MCE) have been investigated. It is found that DyScO 3 single crystal possesses an Ising-like antiferromagnetic magnetic structure below T N ∼3.5 K with the Ising easy axes lying in the ab plane. Meanwhile the strong magnetic anisotropy was observed in DyScO 3 single crystal. In the magnetic field changes of 0–20 kOe and 0–50 kOe, the maximum magnetic entropy changes of 17.04 J/kg K and 21.18 J/kg K were obtained along the b axis, with the corresponding refrigerant capacity (RC) values of 128.62 J/kg and 417.33 J/kg, respectively. With magnetic fields of only 10 kOe and 20 kOe imposed, it was noteworthy that the prominent rotating magnetic entropy changes of 8.49 J/kg K and 16.94 J/kg K at 9.5 K were observed by rotating the DyScO 3 single crystal within the bc plane, respectively. The prominent low-field rotating MCE indicates DyScO 3 single crystal can be used as an excellent potential candidate for low-field rotating magnetic refrigeration near the liquid helium temperature, which is a simpler way by rotating the refrigerants under a low constant magnetic field instead of the general method of changing the imposed magnetic field. Highlights • Magnetic anisotropy, MCE and RMCE were investigated in DyScO 3 single crystal. • − Δ S M max value is 17.04 J/kg K along the b axis under Δ H of 0–20 kOe. • The − Δ S M R values are 8.49 J/kg K and 16.94 J/kg K in the bc plane under 10 kOe and 20 kOe respectively. [ABSTRACT FROM AUTHOR]

The fundamental problem of point defects under different phase equilibrium conditions in zircon (ZrSiO 4 ) is carried out by first-principles calculation. The formation energies with the structural deformation of various native defects, i.e., single vacancy, interstitial, Frenkel and Schottky pairs at different charge states are calculated, which agree well with the available results. We identify V O 2 + shows an important role in non-stoichiometric regime of ZrSiO 4− x ( x  < 1). When Fermi level ( ε F ) locates close to the CBM, the V Zr 4 − becomes more easily observed than V O 2 + in O-rich environment. In turn, the most abundant interstitial defects are I Zr 4 + and I Si 4 + . The non-interacting Si Frenkel-pair, made of the association of quadruply charged defect in energy of 5.947 eV, is more likely to form than other type of Frenkel-pairs. By formation the complex defects associating partial and full Schottky defects requires higher formation energy. These results provide a good reference to understand storage state as well as disposal of excess weapons-grade Pu and high-actinide wastes. [ABSTRACT FROM AUTHOR]

Platinum-containing multimetallic catalysts supported on carbon materials have become one of the main choices for direct ethanol fuel cells (DEFCs) due to their high catalytic activity for the ethanol oxidation reaction (EOR). In this study, a platinum-bismuth alloy catalyst (PtBi@CA) with uniform distribution and small particles was provided by a one-step reduction method without the addition of structure directing agents and stabilizers. In the half-cell test, PtBi@CA(50−50) with the smallest crystallite size has high peak current density and pseudo-steady current density of 64.336 mA/cm2 and 0.096 mA/cm2, respectively, which is 11.22 times and 1.85 times the high of the most advanced commercial carbon-supported platinum catalysts (Pt/C). The method is simple and feasible, greatly reduces the amounts of precious metals, and has broad application prospects in the synthesis of anode electrocatalysts for direct ethanol fuel cells. • A simple one-step reduction method without the addition of structure directing agents and stabilizers synthesis to obtain PtBi@CA electrocatalysts. • The amount of precious metal Pt is effectively reduced. • Alloy-containing electrocatalysts with both fine electrocatalytic activity and durability towards ethanol oxidation. [ABSTRACT FROM AUTHOR]