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Homogenous ultra-fine SnO 2 /TiO 2 particles encapsulated into carbon nanofibers (SnO 2 /TiO 2 @CNFs) with a uniform and ordered one-dimensional fibrous structure are fabricated through facile electrospinning technique and subsequent heat treatments, which are confirmed by XRD, Raman, TG, SEM, TEM, and XPS analyses. The battery performance reveals that the SnO 2 /TiO 2 @CNFs-1.5:1 (1.5:1 denotes the mole ratio of SnO 2 to TiO 2 in the carbon nanofibers) electrode displays the optimal electrochemical properties among the whole samples, which can deliver the initial charge and discharge specific capacity of 1061.2 and 1494.8 mAh/g with a coulombic efficiency of 71.0% at 100 mA/g, and exhibit a remarkable specific capacity of 766.1 mAh/g after 200 cycles. Moreover, the SnO 2 /TiO 2 @CNFs-1.5:1 electrode displays a high pseudocapacitive contribution of 73.9% at the scan rate of 2 mV/s and the lithium ion diffusion coefficient of approximately 1.20 × 10−15 cm2 s−1. The excellent electrochemical performance of the SnO 2 /TiO 2 @CNFs-1.5:1 electrode is closely correlated with the synergetic effect of the proper amount of TiO 2 that enhances the electrochemical stability of the electrode and provides fractional capacity, and the flexible and conductive carbon nanofiber matrix that accommodates volume changes and increases overall electronic conductivity. The detailed investigations of the as-prepared electrode materials by a facile electrospinning process may pave possible instructions for the next generation SnO 2 -based anodes and other related electrospun anodes for the energy storage device. [ABSTRACT FROM AUTHOR]

In this study, Ni–SiC composite coatings with improved wear and corrosion resistance were obtained by ultrasonic electrodeposition (UED) method. The microstructure, microhardness, corrosion and abrasion resistance, and sectional composition distribution of the composite coatings were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical workstation, Vickers microhardness testing, and wear testing. AFM and HRTEM results revealed compact surface structure of Ni–SiC composite coating prepared by UED. Mean diameter of Ni crystals was 68.4 nm, whereas that of SiC nanoparticles present within the composite was 26.7 nm. According to XPS data, contents of Si in UED deposited Ni–SiC composite coating were approximately 23.7 at.%, whereas that of Ni was about 46.8 at.%. Ni–SiC composite coating deposited via UED method exhibited largest microhardness (715.7 HV) compared to other coatings, whereas nickel coating had mean microhardness of 485.8 HV. I corr and E corr values of Ni–SiC composite coatings deposited via UED were 1.13 × 10−3 mA/cm2 and −0.311 V, respectively, indicating optimal level of corrosion resistance. Besides, surface morphological analysis of the coating revealed it to be glossy with only minor surface scratches, exhibiting the best wear resistance. [ABSTRACT FROM AUTHOR]

In this manuscript, Ni–TiN thin coatings were deposited on 45 steel substrate surfaces using a magnetically assisted pulse electrodeposition (MAPE) technique. The surface topographies, chemical compositions, microstructures, microhardnesses, and corrosion properties of the Ni–TiN thin coatings were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), scanning probe microscopy (SPM), triboindenter in-situ nanomechanical testing, as well as corrosion and wear testing. Results indicated that the Ni grain size in the Ni–TiN thin coatings gradually decreased as the grain size of TiN decreased from 180 nm to 32 nm. The mean sizes of TiN nanoparticles and Ni grains in the NT32 thin coating were 41.5 nm and 379.2 nm, respectively. The microhardness of NT180 was the lowest among all three coatings with a mean value of 597.2 HV. Conversely, the mean microhardness of the NT32 thin coating was the highest at 902.9 HV. The size of the TiN particles had a significant effect on the corrosion properties of the Ni–TiN thin coatings, and the corrosion curve of the thin coating of NT32 slowly grew throughout the experiment. Under the same wear test conditions, the NT180 coating showed higher wear mass loss, while the wear mass loss of the NT32 thin coating was the lowest at 36.4 mg. [ABSTRACT FROM AUTHOR]