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Lithium metal has been considered as the most ideal anode in lithium based batteries due to its high specific theoretical capacity and lowest working potential. Nevertheless, the growth of dendritic or mossy Li, the crush of solid electrolyte interface (SEI) layer and the successive reactions between the fresh Li metal and electrolytes hinder the commercialization of Li metal anode. In this paper, we utilize an environmental–friendly and low–cost one–step facile vacuum distillation approach to fabricate the 3D porous Cu current collector from commercial brass foil (Cu–Zn alloy) for Li metal anodes. The continuous porous 3D Cu skeleton is obtained after the vacuum distillated the low boiling point Zn (907 °C) component. The voids of the 3D porous copper can be easily regulated by adjusting the distillation temperature and time. As a current collector, the as–prepared 3D porous copper can inhibit the growth of Li dendrite and mitigate the huge volume change of Li metal anode during cycling process, resulting in stable SEI layer and electrode structure. As a result, the 3D porous Cu current collector can achieve a steady Coulumbic efficiency after 120 cycles at 0.52 mA cm −2 and for more than 80 cycles at 1.04 mA cm −2 with much reduced polarization. A long lifespan of 800 h is attained in the symmetric Li|Li@Cu battery, and it also indicates the potential for practical application when the Li@Cu|Li(NiCoMn)O 2 full battery is built. More promisingly, such a vacuum distillation method is plain and simple to be combined with current commercial technique of Li metal anode manufacture using a Cu current collector, exhibiting great potentials to accelerate the commercialization lithium metal based (such as Lithium–sulfur and Lithium–air) batteries and the development of high–energy lithium–ion batteries. [ABSTRACT FROM AUTHOR]

Highlights: [•] We prepared controlledly the silver nanoparticles on TiO2/SiO2 film by the facile photoreduction under the aid of structure-directing agents. [•] We studied the effect of silver loading on the antibactierial behavior of TiO2 film and optimized the content of silver. [•] We extended the route to fabricate other metals on substrates. [ABSTRACT FROM AUTHOR]

Abstract: MnCO3 microstructures, including 2.3μm microplates with the thickness of 200nm and 3.1μm microspheres stacked with 50nm-thick sheets, were hydrothermally prepared in the assistance of sodium dodecyl benzene sulphonate (SDBS) and dodecyl sulfonic acid sodium (SDS), respectively. With the as-synthesized MnCO3 as precursors followed by annealing at 400°C for 4h, mesoporous γ-MnO2 microplates and microspheres with the pore size of 4–50nm, which basically preserved the initial shapes, were obtained. The Brunauer–Emmett–Teller surface areas of the as-prepared γ-MnO2 microplates and microspheres were 52.1m2 g−1 and 50.2m2 g−1, respectively. The electrochemical property tests over Li+ batteries showed that the initial discharge capacity of γ-MnO2 microplates and microspheres were 1997mAhg−1 and 1533mAhg−1. Noticeably, even after 100cycles, the discharge capacity of γ-MnO2 microplates was still as high as 626mAhg−1, indicating the decent cycle behavior. In addition, mesoporous γ-MnO2 was also applied as adsorbents in water treatment, and γ-MnO2 microplates and microspheres could remove about 55% and 80% of Congo red. [Copyright &y& Elsevier]

Abstract: Porous soft magnetic material is a member of soft magnetic material family having large surface area. This kind of material has vast potential in the surface-related applications. In this paper, a kind of maghemite (γ-Fe2O3) with large surface area, 82.7m2/g, specifically, was obtained by the solvothermal method and subsequent calcining process. As shown in the test results, the maghemite microsphere has no magnetic memory in the magnetic field since the residual magnetization is 0.7emu/g. In the waste water treatment process, Rhodamine B, a model organic pollutant in the water, was removed through the adsorption and desorption cycles by the maghemite microspheres. The maghemite microspheres in the water can be recycled easily by a magnetic separation procedure and regenerated in ethanol at room temperature. [Copyright &y& Elsevier]

A systematic overview of dealloying technique in electrochemical energy storage is presented. [Display omitted] • A review specialized dealloying technique in energy storage. • Characters, fundaments, and advantages of dealloying technique. • Dealloying techniques, including chemical, electrochemical, and vapor dealloying. • 0D, 1D, 2D, and 3D materials fabricated by dealloying technique. • Applications, challenges and future development of dealloying technique in energy storage. Nanomaterials have promising applications in catalysis, filtration, hydrogen storage, sensors, automobile exhaust treatment, and energy storage and conversion, etc. However, scalable and economic fabrication of nanomaterials remains a challenge. In the past century, the world has witnessed successful industrialization of nanoporous Raney nickel in thousands of tons per year by dealloying method. With the advantages of low cost, scalable fabrication and controllable structure, dealloying technique has attracted more attention and gained wider applied in numerous areas. This review attempts to summarize the recent progress in development of dealloying technique, with special emphasis on synthetic materials (0D, 1D, 2D, 3D) and advanced applications, including lithium-ion batteries, lithium-oxygen batteries, lithium-sulfur batteries, lithium-metal batteries, zinc-metal batteries, sodium-ion batteries, magnesium-ion batteries, potassium-ion batteries, aluminum-ion batteries, aluminum-carbon dioxide batteries, and supercapacitors, etc. The advantages, theoretical research, and influence factors of dealloying technique are also analyzed. Besides, key scientific issues and prospective directions of dealloying technique are also discussed. We believe this review may attract more researchers in relevant fields and offer some guide for the future development of dealloying technique. [ABSTRACT FROM AUTHOR]

Abstract: A Cu@carbon (Cu@C) spherical core–shell structure has been synthesized from carbonaceous matrices containing embedded copper particles by thermal treatment at 600°C under an argon atmosphere. The matrices are prepared by reducing CuCl2 with vitamin C (VC) in the existence of polyacrylamide (PAM) at 180°C, accompanied by the partial carbonization of VC. It is found that small Cu nanoparticles with diameters of ∼3nm homogeneously disperse in the carbonaceous matrices. Subsequent thermal treatment at 600°C under an argon atmosphere leads to the diffusion of these Cu nanoparticles and further carbonization of carbonaceous matrices to form a Cu@C core–shell structure. The core–shell ratio can be controlled by varying the dose of CuCl2, VC, or PAM. It is found that the carbon shell can effectively shield the metallic Cu core from oxidation in the mixed solution of dilute hydrogen peroxide and nitric acid. [Copyright &y& Elsevier]

Abstract: Fe3O4 hollow microsphere chains with lengths of 8–11 μm have been solvothermally synthesized in the mixed solution of glycerol and water with 1 M NaOH. The hollow microspheres have diameters in the range 0.7–1 μm, and the thickness of the shells is 150–300 nm. The shell of the hollow microspheres is constructed by octahedrons of 100–170 nm. However, when the concentration of NaOH is adjusted to 3 M, the octahedron chains with lengths of 30–50 μm can be obtained. The magnetic saturation values of hollow microsphere chains and octahedron chains are 88.1 and 102.4 emu/g at room temperature, respectively. [Copyright &y& Elsevier]

Abstract: The phase transition of CdSe nanocrystallines from zinc blende to wurtzite phase can be controlled by varying the volume ratio of ethanolamine (EA) and water (WA) in their mixed solution and the morphologies of the CdSe nanocrystals are controlled simultaneously. The phase transition has been demonstrated by XRD patterns and HRTEM images. The samples are investigated by Raman spectrum. The Raman shifts of the samples show a gradual blue shift with the gradual transformation from zinc blende to wurtzite CdSe phase. This method is convenient and controllable which can provide a strategy way to control the phase and morphology of the nanomaterials and study their phase transitions in nanoscale field. [Copyright &y& Elsevier]