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The separator modification has been considered to be the most effective approach to obtain high-stability lithium–sulfur batteries (LSBs). Therefore, a separator with an ultralight modification layer plays an indispensable role to obtain LSBs with high specific capacity and high energy density. Herein, we report a novel modified separator with an ultrathin and lightweight MnO2 functional layer (500 nm, 0.1 mg cm−2), which was grown in situ on a Celgard-2400 separator (MnO2@PP) via a facile hydrothermal reaction. The MnO2@PP separator effectively suppressed the shuttle of lithium polysulfides (LiPSs) and improved the redox process. In addition, the strong chemical affinity of MnO2 for LiPSs was also verified by first-principles calculations. Benefiting from these advantages, the cell with the MnO2@PP separator delivered a high rate performance of 759 mA h g−1 at 2.5 C and an initial capacity of 825 mA h g−1 with a retention of 684 mA h g−1 after 400 cycles at 1.25 C. Even with a high sulfur loading of 6 mg cm−2, the obtained cell exhibited a reversible capacity of 747 mA h g−1 after 150 cycles. [ABSTRACT FROM AUTHOR]

Abstract: Pure titanium was subjected to surface modification in order to improve its bioactivity. Samples wet-polished by abrasive paper were hydrothermally treated in 0.1mol/l MgCl2 solutions with different pH values (5.5, 7.5 and 9.5) at 200°C for 24h. By forming nano-sized anatase precipitations, hydrothermal treatment increased the thickness of the oxide layer obviously and Mg was found to distribute all through the oxide layer. Treatment in solution with a low pH formed Tih name="sbnd" />Mg bond as MgTiO3, whereas, high pH induced Mg(OH)2 precipitation onto the samples. Cell attachment and spreading were improved on samples treated in the solution of pH 5.5. As treatment solution pH rose, protein (Bovine Serum Albumin, BSA) adsorption on treated samples increased; however, initial osteoblast attachment and spreading were impaired. It is suggested that, hydrothermal treatment in MgCl2 solution can improve the bioactivity of titanium by immobilizing Mg into oxide layer, however, the chemical state and amount of Mg should be well controlled. [Copyright &y& Elsevier]

Abstract: Porous titanium oxide film was prepared by micro-arc oxidation (MAO) method on the surface of titanium alloy in electrolyte containing Ca and P. Surface characterizations of the film were carried out using X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) before and after immersion in Hank''s solution. Electrochemical behaviors and corrosion resistance were studied by electrochemical techniques. The film was mainly composed of titania, α-tricalcium phosphate (α-TCP) and amorphous Ca–P compounds. α-TCP and amorphous compounds could transformed into hydroxyapatite (HA) when immersed in Hank''s solution. MAO film showed higher corrosion potential and lower corrosion current than the titanium alloy and its chemical stability was slightly changed after formation of HA. Fitted electrochemical impedance spectroscopy (EIS) data indicated that after immersion for 2weeks the MAO film kept good corrosion resistance. Porous TiO2 film on titanium alloy by MAO method showed good chemical stability in Hank''s solution and the transformation of Ca–P compounds into HA indicated that MAO was an effective method for preparing titanium alloys as bioactive artificial bone substitute even when Ca and P in the tissue environment were not abundant. [Copyright &y& Elsevier]

The separator modification has been considered to be the most effective approach to obtain high-stability lithium-sulfur batteries (LSBs). Therefore, a separator with an ultralight modification layer plays an indispensable role to obtain LSBs with high specific capacity and high energy density. Herein, we report a novel modified separator with an ultrathin and lightweight MnO2 functional layer (500 nm, 0.1 mg cm-2), which was grown in situ on a Celgard-2400 separator (MnO2@PP) via a facile hydrothermal reaction. The MnO2@PP separator effectively suppressed the shuttle of lithium polysulfides (LiPSs) and improved the redox process. In addition, the strong chemical affinity of MnO2 for LiPSs was also verified by first-principles calculations. Benefiting from these advantages, the cell with the MnO2@PP separator delivered a high rate performance of 759 mA h g-1 at 2.5 C and an initial capacity of 825 mA h g-1 with a retention of 684 mA h g-1 after 400 cycles at 1.25 C. Even with a high sulfur loading of 6 mg cm-2, the obtained cell exhibited a reversible capacity of 747 mA h g-1 after 150 cycles.

Hydrocarbon contamination accumulated on titanium (Ti) implant surfaces during storage and sterilization is unavoidable and difficult to remove. It impairs the bioactivity of implants, restricts initial interactions between implants and the surrounding biological environment, and has become a common challenge for Ti implants. To overcome this problem, sterilization was considered as the final surface modification and a novel method, hydrothermal sterilization (HS), was proposed. Briefly, stored sandpaper-polished Ti specimens were sterilized in a glass container with pure water at 121 °C for 20 min and kept in the same water until utilization. As a control, another group of specimens was sterilized with conventional autoclaving (AC) at 121 °C for 20 min and stored in sterilization pouches after being dried at 60 °C. Compared with AC, HS deposited numerous nano-sized particles on the substrates, reduced the atomic percentage of the surface carbon, and transformed the Ti surface to a super hydrophilic status. HS also increased the attachment rate, spread, proliferation, and the mineralized nodule areas of rat bone marrow-derived osteoblasts. These results suggest that HS enhances the bioactivity of Ti implants for osteoblasts, and that this biofunctionalization was attributed to nanostructure construction, hydrophilic conversion, and the effective removal of hydrocarbons. Hydrothermal sterilization is proposed to be used as a universal sterilization method for all kinds of titanium implants without apatite coating., Competing Interests: The authors declare no conflict of interest.