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α-Ga2O3 microrods was deposited on carbon cloth (CC) using a hydrothermal process followed by a high-temperature annealing in air. The microstructure of the obtained Ga2O3/CC composite electrodes were characterized with scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Their electrochemical performances were tested with electrochemical impedance spectroscopy (EIS), Mott-Schottky (MS), cyclic voltammetry (CV) and galvanostatic charge/discharge techniques (GCD). By comparing the electron densities and mobilities of the Ga2O3/CC electrodes prepared with different hydrothermal durations, the doping mechanisms of point defects in α-Ga2O3 were revealed. The point defects in α-Ga2O3 including Ga-oxygen vacancies (Ga-VO), gallium vacancies (VGa), and VGa-VO complexes were all identified as the scattering centers. By extending the hydrothermal duration to more than 6 h, the electronic conductivity of the Ga2O3/CC electrode was enhanced by reducing the number of point defects in α-Ga2O3. The Ga2O3/CC-6h aqueous symmetrical supercapacitor (SC) showed a remarkable increase in the electrochemical performance by exhibiting a specific areal capacitance of 1394 mF cm−2 at 0.5 mA cm−2, with 67% of the capacitance retained when the current density was increased to 20 mA cm−2, and 76.5% of capacitance retention after 20,000 cycles under a current density of 10 mA cm−2. The point defect mechanism identified in the article would pave the way to develop novel energy storage devices based on α-Ga2O3 in the future. [ABSTRACT FROM AUTHOR]

Ferroferric oxide (Fe3O4) is regarded to be a promising high-capacity anode material for LIBs. However, the capacity attenuates fast and the rate performance is poor due to the dramatic pulverization and sluggish charge transfer properties. To solve these problems, a simple in situ encapsulation and composite method was successfully developed to construct carbon nanotube/nanorod/nanosheet-supported Fe3O4 nanoparticles. Owing to the hierarchical architecture design, the novel structure Fe3O4@C nanocomposites effectively enhance the charge transfer, alleviate pulverization, avoid the agglomeration of Fe3O4 nanoparticles, and also provide superior kinetics toward lithium storage, thereby showing significantly improved reversibility and rate performance. The carbon nanotube/nanorod supported core-shell structure Fe3O4@C nanocomposite displays outstanding high rate capability and stable cycling performance (reversible capability of 1006, 552 and 423 mA h g−1 at 0.2, 0.5 and 1 A g−1 after running 100, 300 and 500 cycles, respectively). [ABSTRACT FROM AUTHOR]

Abstract: Pd-membranes in combination with water gas shift (WGS) reactors are considered as a cost and energy efficient technology for CO2 capture in natural gas or coal-fired power stations. An important step towards realization of a full-scale membrane reactor is the demonstration of a scaled-down version. This paper describes the realization of a scaled-down membrane module, which is able to generate a hydrogen flux of approximately 12 Nm3/m2.hr at a hydrogen recovery of 95% and an operating temperature of 400°C under 30bar of NGCC-gas composition as feed stream and 6bar N2 sweep stream. [Copyright &y& Elsevier]

A CaO- Al2 O3- SiO2 ( CAS)-based glass interlayer was developed for joining of porous alumina membrane tubes with dense alumina in this work. The results indicated that the interfacial microstructure of the joint was highly sensitive to the quench rate from the joining temperature, which rendered crystallization of CaTiSiO5 at a fast quench rate but CaAl2 Si2 O8 at a slow quench rate due to the interfacial reaction between the CAS glass interlayer and the substrate. An extra crystallization treatment during quench, i.e., dwelling at 800°C-900°C for 2 h, produced a multiphase interlayer consisting of LiAlSi2 O6, CaTiSiO5, and CaAl2 Si2 O8. All joints were evaluated by the thermal shock test. The results showed that the LiAlSi2 O6-containing joint interlayer had much lower thermal shock resistance than those without LiAlSi2 O6. [ABSTRACT FROM AUTHOR]

Abstract: Spinel lithium titanate, Li4Ti5O12, with novel hollow-sphere structure was fabricated by a sol–gel process using carbon sphere as template. The effect of the hollow-sphere structure as well as the wall thickness on the Li storage capability and high rate performance was electrochemically evaluated. High specific capacity, especially better high rate performance was achieved with this Li4Ti5O12 hollow-sphere electrode material with thin wall thickness. It is believed that this macroporous hollow-sphere structure has shortened the Li diffusion distance, increased the contact area between Li4Ti5O12 and electrolyte, and also led to better mixing of the active material with AB. All these factors have resulted in the good rate capability of the hollow-sphere structured Li4Ti5O12 electrode material. [Copyright &y& Elsevier]

Abstract: The lithium storage capability and high rate performance of nanocrystalline anatase TiO2 electrodes are highly dependent on the particle sizes. The electrode made from a very fine anatase powder of 6nm exhibited the highest capacity even at high current rates. It is believed that increasing the specific surface area of the nanocrystalline anatase electrodes has increased the weight ratio of the atoms resided near or on the surface layers and hence improved the surface Li storage; whereas decreasing the particle size has reduced the transport length for Li insertion in the bulk of anatase phase, and so made the Li insertion more efficiently. Besides that, it is found that the specific capacity contributed by the surface Li storage was very stable upon cycling or increasing the current rate; whereas the short Li diffusion length could greatly facilitate the Li insertion/extraction in/from the bulk of the anatase electrode. These two features of nanocrystalline anatase electrodes resulted in very good cycle performance. [Copyright &y& Elsevier]

Highlights: [•] The structured TiO2–SiC were prepared using a composite sol–gel method. [•] The p-type SiC foam support was used in photocatalysis for the first time. [•] The TiO2–SiC enhanced the photocatalytic efficiency by a synergistic effect. [ABSTRACT FROM AUTHOR]