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MOFs-derived metal oxides composites nanofibers composed of MOFs-derived metal oxides nanoparticles and interconnected carbon nanofibers exhibited excellent lithium storage performance. • MOFs-derived metal oxides composites nanofibers with a 3D network were synthesized. • Carbon nanofibers improve the conductivity and structural integrity of based-material. • MOFs-derived composites nanofibers exhibit superior electrochemical performances. The lithium storage performance of metal oxides often suffer rapid capacity fading and poor rate performance due to their huge volume expansion during repeated charge and discharge processes. Herein, a facile strategy was adopted for constructing a three-dimensional (3D) interconnected conductive network. Metal-organic frameworks (MOFs)-derived metal oxides (Fe 2 O 3 , ZnO) were inlayed in carbon nanofibers through electrospinning and subsequent carbonization processes. As lithium-ion storage materials, the MOFs-derived metal oxide composite nanofibers exhibited a high specific capacity and an excellent rate capability due to the unique structural characteristics of high electrical conductivity, additional Li-storage sites, and defined frameworks. The Fe 2 O 3 @polyacrylonitrile (PAN) and ZnO@PAN composite nanofibers deliver high initial specific capacities of 1571.4 and 1053.8 mAh g−1 at 50 mA g−1, respectively. Moreover, Fe 2 O 3 @ PAN and ZnO@PAN composite nanofibers retained reversible specific capacities of 506.6 and 455.4 mAh g−1 at 1000 mA g−1 after 500 cycles, respectively. Additionally, the diffusion kinetics analysis indicated a relatively fast Li-ion diffusivity for the composite nanofibers. [ABSTRACT FROM AUTHOR]

The Co@BN core–shell structure boosts dye-sensitized photocatalysis under shell by confined effect and improvement of the tandem electron transfer. • High EY-sensitized photocatalytic hydrogen evolution activity was achieved. • Enhanced adsorption of EY and Co/BN Schottky junction promotes the electron transfer. • The confined space was a nanoreactor boosting the reduction of H+ to H 2 under shell. • The magnetic recyclability makes Co@BN favorable for its practical application. The Co@BN core–shell nanostructure of Co core and boron nitride (BN) shell was prepared through a facile one-step thermal treatment. The as-prepared Co@BN nanocomposites exhibited excellent dye-sensitized photocatalytic hydrogen evolution activity (13.78 mmol h−1 g−1) with visible light and the apparent quantum yield was 1.15%. The enhanced adsorption of EY on the BN shell and the Co/BN Schottky junction facilitate the tandem transfer of photo-generated carriers to the Co surface. Moreover, the core–shell interface serves as a nanoreactor boosting the reduction of H+ to H 2 on the Co surface. Additionally, the magnetic recyclability makes Co@BN favorable for its practical application. This work extends the application of the "photocatalysis under shell" and has potential in dye-sensitized solar cell. [ABSTRACT FROM AUTHOR]

Abstract: TiO2, which is high in refractive index and dielectric constant, plays an important role in the fields of optics and electronics. In this work, TiO2 films were prepared on glass substrates by the technique of ion beam assisted electron beam evaporation. The films were deposited at 50, 150 and 300°C, respectively. Then the as-deposited TiO2 films were annealed at 450°C for 1h in vacuum atmosphere. Structures and optical properties of TiO2 films were characterized by XRD, SEM, ellipsometry and spectrophotometer. As a result, the structure and the refractive index of films were improved by both the annealing and the increasing of the deposition temperature. The UV–vis transmittance spectra also confirmed that the deposition temperature has a significant effect on the transparency of the thin films. The highest transparency over the visible wavelength region of spectra was obtained at the deposition temperature of 300°C. The allowed direct band gap at the deposition temperature ranging from 50 to 300°C was estimated to be in the range from 3.81 to 3.92eV. [Copyright &y& Elsevier]