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AlCrN coatings were deposited on 316L stainless steel by multi-arc ion plating. The phase structures were controlled and optimised by vacuum annealing at 700 °C, 800 °C, and 900 °C, each for 2 h. The microstructures and morphologies of these coatings were examined by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscope, in association with adhesion strength measurement, residual stress measurement and potentiodynamic polarisation with 3.5% NaCl and 10% H 2 SO 4 solutions. Results show that the solid solution hcp-(Cr, Al)N phase of as-deposited AlCrN coatings decomposes into hcp-AlN and CrN phases, then further decompose into N and Cr with increasing annealing temperature. Metal particles and droplets on the coating surface were gradually removed simultaneously when compared with as-deposited coatings. The highest adhesion strength was obtained after annealing at 700 °C. It decreased with increasing annealing temperature due to the σ-FeCr phase and Cr 2 N phases, and the residual stress decreasing. The potentiodynamic polarisation measurements showed that the corrosion resistance of such coatings was significantly improved after annealing: the coatings annealed at 800 °C showed the best protective efficiency because some corrosion resistance phases (h-AlN, Al 2 O 3 , CrN, and Cr 2 N) were generated. [ABSTRACT FROM AUTHOR]

Three-dimensional hybrids of cobalt oxide (CoO) and graphene frameworks are fabricated via a facile hydrothermal self-assembly process. By adjusting the time of the hydrothermal treatment, the morphologies of the CoO components can be modified from rods to nanoparticles, which further manifest influences on the electrochemical performance of the hybrids. As the anode in lithium-ion battery, the hybrid loaded with spherical CoO nanoparticles exhibits the highest reversible capacity of 1148 mA h g at 100 mA g for 100 cycles among the three samples. Even at a high current density of 5000 mA g, its reversible capacity is still kept at 600 mA h g, outperforming the reported hybrids of CoO and graphene. [ABSTRACT FROM AUTHOR]

3D hierarchical tin oxide/graphene frameworks (SnO2/GFs) were built up by the in situ synthesis of 2D SnO2/graphene nanosheets followed by hydrothermal assembly. These SnO2/GFs exhibited a 3D hierarchical porous architecture with mesopores (≈3 nm), macropores (3-6 μm), and a large surface area (244 m2 g−1), which not only effectively prevented the agglomeration of SnO2 nanoparticles, but also facilitated fast ion and electron transport in 3D pathways. As a consequence, the SnO2/GFs exhibited a high capacity of 830 mAh g−1 for up to 70 charge-discharge cycles at 100 mA g−1. Even at a high current density of 500 mA g−1, a reversible capacity of 621 mAh g−1 could be maintained for SnO2/GFs with excellent cycling stability. Such performance is superior to that of previously reported SnO2/graphene and other SnO2/carbon composites with similar weight contents of SnO2. [ABSTRACT FROM AUTHOR]

Review: 130 refs. [ABSTRACT FROM AUTHOR]

Using an efficient synthetic strategy,a novel class of 1,2-diazine-embeddedperylenes, namely 1,2,7,8-tetraazaperylene derivatives, have beensuccessfully synthesized. These molecules were fully characterizedby X-ray diffraction analysis, optical spectroscopy, and electrochemistry.The low-lying lowest unoccupied molecular orbital (LUMO) level ofthese molecules suggests their potential as good electronic acceptors. [ABSTRACT FROM AUTHOR]