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Abstract: Hydrogen permeation flux of Ni–BaZr0.1Ce0.7Y0.2O3– δ cermet (ceramic–metal composite) was measured in an H2S-containing atmosphere at 973K. In 30 and 60ppm H2S, the hydrogen permeation flux decreased by about 20% and 30%, respectively. After the removal of H2S, the hydrogen permeation flux recovered partially in several hours and then remained stable. After exposing to 60ppm H2S, X-ray diffraction (XRD) analysis revealed a little formation of Ni3S2, BaS, and doped CeO2. Thermodynamic calculation results showed that the critical value of pH2S/pH2 for the formation of Ni3S2 was about 0.0066 at 973K, suggesting that the Ni3S2 found after testing was formed in the cooling process. The reaction between H2S and BaCeO3 was rather weak and could not be the cause of the performance loss. Analysis of poisoning and regeneration behavior suggested that the adsorption of sulfur on nickel surface caused the performance loss. [Copyright &y& Elsevier]

Abstract: Screen-printing technology was employed to fabricate BaCe0.8Sm0.2O3−δ (BCS) electrolyte membranes on porous NiO–BCS anode substrates. With a mixture of BCS and La0.7Sr0.3FeO3−σ as cathode, a single cell with 16μm thick BCS electrolyte generated maximum power densities of 222, 141, 72mW/cm2 at 700, 650 and 600°C, respectively. After the electrolyte surface was modified by spray coating, the single cell with 16μm thick BCS electrolyte generated maximum power densities of 352, 241, 125mW/cm2 at 700, 650 and 600°C, respectively. The improved performance of the fuel cell was attributed to the surface modification by spray coating promoting the adherence of the cathode to electrolyte, which was confirmed by both scanning electron microscope (SEM) observation and impedance measurement. The results illustrate that screen-printing technology with spray coating is a simple and low cost method for preparing thin electrolyte membranes of protonic ceramic fuel cells. [Copyright &y& Elsevier]

Electrospinning is the most common and promising method to prepare nanofibers. The nanofibers produced have the advantages of a small average diameter, high specific surface area, and high porosity. In recent years, fibers have been used as cathodes and anodes in solid oxide fuel cells (SOFCs). Owing to the unique microstructure and electron and ion conduction properties of nanofiber electrodes, the electrocatalytic activity is significantly increased, and as a consequence, the electrochemical performance of the fuel cell is substantially improved. This paper mainly reviews the research progress of electrospinning technology in the SOFCs field. In addition, the effects of various processing parameters on the fiber structure are summarized from the perspective of processing variables. The electrodes prepared by the electrospinning method in recent years are primarily introduced. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A double perovskite phase SmBaCo2O6−δ powder was successfully synthesized by the citric acid–nitrate gel combustion process after calcining at 900°C for 4h, using undissolved and relatively inexpensive Co3O4 as a starting material for the first time. TGA–DTA and XRD results revealed the formation mechanism of the double perovskite phase. The BaCoO3−δ was generated firstly, then the formation of Ba-doped SmCoO3−δ occurred, and finally Sm3+ and Ba2+ were distributed orderly, obtaining SmBaCo2O6−δ with a double perovskite phase. SEM analysis indicated that Co3O4 might play as a “template” in the synthesis process of SmBaCo2O6−δ via this special method. The conductivity of SmBaCo2O6−δ was still higher than 200Scm−1 at 850°C, which is adequate as a cathode material for Solid Oxide Fuel Cells (SOFCs). [Copyright &y& Elsevier]

Magnetic garnets (MG) are insulators with superior magnetic and optical properties, such as high Curie temperature, highly tunable bulk perpendicular magnetic anisotropy (PMA), ferrimagnetic nature with low net moment, extremely low Gilbert damping, strong magneto-optic effects, optical nonreciprocity and low optical loss, etc. Consequently, these attributes make them particularly suitable for the applications in the next generation spintronic and photonic devices, which exhibit low energy consumption, room temperature fast operation speed and high integration density. Significant efforts have already been carried out for the development of high quality MG thin films as well as exploiting the applications of these MG thin films in novel spintronic and photonic devices. In this review, we have summarized the recent progresses in the related subjects listed as follow: (1) growth of epitaxial MG thin films on non-magnetic garnet substrates, including yttrium iron garnet (YIG) thin films with ultra-low damping on gadolinium gallium garnet (GGG) substrates and MG thin films with PMA on non-magnetic garnet substrates; (2) integration of MG films on non-garnet substrates, including wafer bonding or transfer printing epitaxial high-quality MG thin films on non-garnet substrates and monolithic deposition of MG thin films on non-garnet substrates; (3) applications of MG thin films in spintronics, including preliminary works for realizing of spin-orbit-torque (SOT) driven fast Skyrmion motion, magnetic proximity effect and SOT switching; (4) applications of MG films in photonic devices, including nonreciprocal photonic devices and magneto-nanophotonic devices. [ABSTRACT FROM AUTHOR]

Driven by advances in soft material science, magnetic soft robots have recently attracted significant attention owing to their remarkable reprogramming deformations under magnetic fields, as well as having features distinct from those traditional rigid robots, including mechanical compliance, tether-free actuation, and biocompatibility. In this review, we summarize state-of-the-art progress in magnetic soft materials and robots. First, we present a brief introduction to the recent design and fabrication of magnetic soft materials. Significant progress in magnetic soft robots with reconfigurable structures, innovative actuation technologies, corresponding simulation models, and their sophisticated functions are highlighted. Finally, we discuss promising research directions and the remaining challenges for the future development of magnetic soft robots. • The innovative methodologies of fabrication soft magnetic materials are summarized. • Recent advances of soft magnetic robots with reconfigurable structures are discussed. • The actuation technologies, corresponding simulation models and significant applications are summarized. • The promising research direction along with remaining challenging of this fast-growing area are prospected. [ABSTRACT FROM AUTHOR]

Abstract: A dense hydrogen permeable composite membranes consisting of Ni and BaCe0.7Zr0.1Y0.2O3−δ (BCZY) were fabricated by a packing method at a lower temperature than the powder-mixing method. The results of backscattered electron microscope (BSEM) and scanning electron microscope (SEM)-energy dispersive analysis system of X-ray (EDS) revealed that the membrane derived from the packing method showed the most uniform mixture of the Ni phase and the BCZY phase. The hydrogen permeation measurement showed that a more uniform microstructure would result in higher hydrogen permeation. [ABSTRACT FROM AUTHOR]