Lithium sulfur (Li-S) batteries have drawn much attention as next-generation batteries because of their high theoretical capacity (1672 mAh g − 1), environmental friendliness and low cost. However, several critical issues, which are mainly associated with the polysulfide shuttling effect, result in their poor electrochemical performance. Carbon-modified separators have been introduced to attempt to address these systemic challenges. However, this approach focused only on the suppression of dissolved polysulfides on the cathodic side without considering the further entrapment of polysulfides on the anodic side. In this study, we first designed a multifunctional trilayer membrane comprising a carbon layer and a boron nitride (BN) layer to facilitate the electrochemical performance of Li-S batteries and protect the Li anode from unexpected side reactions. When a BN-carbon separator was employed, the sulfur cathode delivered stable capacity retention over 250 cycles and an excellent specific capacity (702 mAh g − 1) at a high current density (4 C). The BN-carbon separator also facilitated the uniform plating/striping of Li and, thus, suppressed the severe growth of dendritic Li on the electrode; this led to the stable operation of the Li anode with a high Coulombic efficiency and improved cycling performance.

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With shrinkage of the minimum feature size to sub-14 nm, protrusion/dishing issues in chemical mechanical planarization (CMP) processes have become increasingly important to address. In this study, we propose an advanced slurry formulation with a surface active agent to prevent W protrusion during the W CMP process. In the presence of surface active agent, blanket removal rates on both W and SiO2 films showed non-Prestonian behavior at a low threshold pressure, which is explained by adsorption characteristics of the surface active agent on the films. To study the effect of the surface active agent on W protrusion, W-patterned wafers were polished at the threshold pressure. As the concentration of the surface active agent increased from 0 to 12 mM, W protrusion from patterns with line/space widths of 0.5 μm/0.5 μm decreased significantly from 186 to 30 Å. The mechanism on the significant decrease in W protrusion behavior in the presence of the surface active agent is discussed.

The authors first report the three-dimensional (3D) structured CeO 2 -PLA scaffold using a 3D printing methodology. The scaffold is prepared by decorating functional metal-oxide nanoparticles onto the 3D-printed polylactic acid (PLA) platform via an electrostatic interaction and is applied to the applications for photochemical degradation. As-designed CeO 2 -PLA scaffold shows high photocatalytic degradation performance toward methyl orange under a light irradation. Furthermore, the CeO 2 -PLA scaffold shows reasonable degradation performance even after it is washed and reevaluated; this result demonstrates the benefit of 3D-printed CeO 2 -PLA scaffold that it can be recycled several times without losing the catalysts.Three dimensional printing (3D printing) has been in a spotlight due to custom made process, [1] ability to fabricate the complex-shaped object, [2] and open access to hardware and software. [3] Among the several types of 3D printing methods, fused deposition modeling (FDM), especially, is widely implemented owing to its cost-benefit and ease accessability. [4] However, only thermoplastic materials such as polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) can be applied to the FDM printing method; this led to confine application fields to biomedical support [5] and rapid prototype manufacturing. [6] Many attempts have been explored to overcome the material limitation in FDM printing and broaden the application fields. The ABS scaffold decorated with Metal oxide frameworks (MOFs) was demonstrated to expand the application field to dye removal. [7] The 3D metallic scaffold was prepared by atomic transfer radical polymerization and electroless plating method. [2] However, these approaches to prepare 3D scaffolds decorated with various materials still have systematic issues due to the limited selection of materials and the complicated procedure. As metal oxide materials have enormous potentials to various applications including biomedical, [8] catalyst, [9] and energy related devices, [10] the approach to combine metal oxide with 3D-printed object is considered as a solution to address the above-mentioned challenges.Herein, we first report a facile strategy to prepare the metal oxide coated 3D scaffold via electrostatic interactions. Polylactic acid was served as a 3D printing material due to its cost-benefit and harmless properties. The negative surface charge of polylactic acid could provide adsorption site for positively charged material. [11] Additional functional group generated by UVO treatment induces more negative charge on the surface of PLA. [12] CeO 2 , one of positively charged materials, was selected as a coating material. [13] The amount of deposited CeO 2 can be controlled by irradiating UV-Ozone (UVO) onto PLA surface and adjusting the pH of coating suspension. To demonstrate practical application with our methodology, we carried out the photocatalytic dye degradation process using CeO 2 decorated PLA scaffold. CeO 2 decorated 3D printed scaffold shows promising possibility...

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