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© 2019 American Chemical Society. Zinc ion batteries (ZIBs) have attracted extensive attention in recent years, benefiting from their high safety, eco-friendliness, low cost, and high energy density. Although many cathode materials for ZIBs have been developed, the poor stability of zinc anodes caused by uneven deposition/stripping of zinc has inevitably limited the practical application of ZIBs. Herein, we report a highly stable 3D Zn anode prepared by electrodepositing Zn on a chemically etched porous copper skeleton. The inherent excellent electrical conductivity and open structure of the 3D porous copper skeleton ensure the uniform deposition/stripping of Zn. The 3D Zn anode exhibits reduced polarization, stable cycling performance, and almost 100% Coulombic efficiency as well as fast electrochemical kinetics during repeated Zn deposition/stripping processes for 350 h. Furthermore, full cells with a 3D Zn anode, ultrathin MnO2 nanosheet cathode, and Zn2+-containing aqueous electrolyte delivered a record-high capacity of 364 mAh g-1 at a current density of 0.1 A g-1 and good cycling stability with a retained capacity of 173 mAh g-1 after 300 charge/discharge cycles at 0.4 A g-1. This work provides a pathway for developing high-performance ZIBs.

Active carbon/BiOI microspheres were first prepared using a facile one-step solvothermal route from Bi(NO3)3·5H2O, KI, active carbon, and ethylene glycol. The phase structure, morphology, and optical properties of the as-prepared products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, high resolution transmission electron microscopy, and UV-visible diffuse reflectance spectra. HRTEM mapping results showed that within the composites, active carbon particles dispersed well onto BiOI spheres. The apparent variations in binding energies and photocurrent measurement results verified that the interactions between both components are strong. As a consequence, these active carbon/BiOI composites exhibit an enhanced photocatalytic reduction activity of Cr(VI) under visible light (λ > 420 nm) irradiation when compared with pure BiOI. This work can strengthen the application of BiOI-based micromaterials in treating wastewater contaminated by highly toxic and intractable Cr(VI).

© 2017 Elsevier Ltd Rechargeable zinc ion battery is considered as one of the most potential energy storage devices for large-scale energy storage system due to its safety, low-cost, high capacity and nontoxicity. However, only a few cathode materials have been studied for rechargeable zinc ion batteries. Here, we firstly report manganese sesquioxide (Mn2O3) with Mn(III) state as cathode material for rechargeable zinc ion battery. The α-Mn2O3 cathode displays a reversible capacity of 148 mAh g−1, which is relatively high among all the reported cathode materials for ZIB. The cathode also exhibits good rate capability and excellent cycling stability with a long cycle life up to 2000 times. The ion storage mechanism of α-Mn2O3 in zinc ion battery was also revealed. The pristine α-Mn2O3 undergoes a reversible phase transition from bixbyite structure to layered-type zinc birnessite during the electrochemical zinc ion insertion and extraction. The results not only benefit for the practical application of rechargeable zinc ion battery, but also broaden the horizons of understanding the electrochemical behavior and mechanism of rechargeable zinc ion batteries.

Synchrotron radiation is an advanced collimated light source with high intensity. It has particular advantages in structural characterization of materials on the atomic or molecular scale. Synchrotron radiation X-ray powder diffraction (SR-XRPD) has been successfully exploited to various areas of hydrogen storage materials. In the paper, we will give a brief introduction on hydrogen storage materials, X-ray powder diffraction (XRPD), and synchrotron radiation light source. The applications of ex situ and in situ time-resolved SR-XRPD in hydrogen storage materials, are reviewed in detail. Future trends and proposals in the applications of the advanced XRPD techniques in hydrogen storage materials are also discussed.

ZnO/Ag nanocomposites with adjustable surface-enhanced Raman scattering performance and photocatalytic activity were synthesized by a photochemical method. The as-prepared samples were investigated using various spectroscopic and microscopic techniques in detail. Solvents play a key role in controlling the morphologies and properties of these nanocomposites. Detection and degradation of organic dyes is studied. It has been found that suitable experimental parameters are crucial to the detection and degradation of organic dyes molecules. The work is of great importance in practical applications based on the surface-enhanced Raman scattering and photocatalytic performance of noble metal/oxide metal nanocomposites, which could be used for detection and degradation of organic dyes and pollutants.