Hierarchically porous carbon-coated ZnO quantum dots (QDs) (~3.5 nm) were synthesized by a one-step controlled pyrolysis of the metal-organic framework IRMOF-1. We have demonstrated a scalable and facile synthesis of carbon-coated ZnO QDs without agglomeration by structural reorganization. This unique microstructure exhibits outstanding electrochemical performance (capacity, cyclability, and rate capability) when evaluated as an anode material for lithium ion batteries.

The lithium-sulfur (Li-S) battery is considered as a promising future energy storage device owing to its high theoretical energy density, low cost of the raw active material (sulfur), and its environmental friendliness. On the other hand, there are still challenging issues for the practical applications of Li-S batteries, including low sulfur utilization, poor cyclability, and rate capability. Although considerable efforts are made to overcome the current obstacles in Li-S batteries, one is still far from meeting the requirements for the commercialization of Li-S batteries. This review outlines the recent progress in Li-S batteries based on novel configurations, such as incorporating functional interlayers/separators beyond the approach for preparing novel cathodes, and discusses the role of the configuration in Li-S batteries. The functions of the newly introduced functional interlayer/separator are highlighted to address the problems of Li-S batteries. From classification of the functions, the perspectives and outlook are presented to rationally design a novel functional interlayer/separator for high-performance Li-S batteries.

We present a colloidal route for the synthesis of ultrathin ZrS(2) (UT-ZrS(2)) nanodiscs that are ~1.6 nm thick and consist of approximately two unit cells of S-Zr-S. The lateral size of the discs can be tuned to 20, 35, or 60 nm while their thickness is kept constant. Under the appropriate conditions, these individual discs can self-assemble into face-to-face-stacked structures containing multiple discs. Because the S-Zr-S layers within individual discs are held together by weak van der Waals interactions, each UT-ZrS(2) disc provides spaces that can serve as host sites for intercalation. When we tested UT-ZrS(2) discs as anodic materials for Li(+) intercalation, they showed excellent nanoscale size effects, enhancing the discharge capacity by 230% and greatly improving the stability in comparison with bulk ZrS(2). The nanoscale size effect was especially prominent for their performance in fast charging/discharging cycles, where an 88% average recovery of reversible capacity was observed for UT-ZrS(2) discs with a lateral diameter of 20 nm. The nanoscale thickness and lateral size of UT-ZrS(2) discs are critical for fast and reliable intercalation cycling because those dimensions both increase the surface area and provide open edges that enhance the diffusion kinetics for guest molecules.

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This study examined the optical and electronic properties of post-annealed Al-doped ZnO ͑ZnO:Al͒ thin films. The lowest resistivity was observed after annealing a sputter-deposited ZnO:Al film at 350°C. X-ray photoelectron spectroscopy revealed a ϳ0.4 eV shift in the Fermi level when the carrier concentration was increased to 1.6ϫ 10 20 cm −3 by Al doping and annealing. The optical band gap increased from 3.2 eV for insulating ZnO to 3.4 eV for conducting ZnO:Al, and was associated with conduction-band filling up to ϳ0.4 eV in a renormalized band gap. Schematic band diagrams are shown for the ZnO and ZnO:Al films.

A disadvantage of 3D isotropic acquisition in whole-heart coronary MRI is the prolonged data acquisition time. Isotropic 3D radial trajectories allow undersampling of k-space data in all three spatial dimensions, enabling accelerated acquisition of the volumetric data. Compressed sensing (CS) reconstruction can provide further acceleration in the acquisition by removing the incoherent artifacts due to undersampling and improving the image quality. However, the heavy computational overhead of the CS reconstruction has been a limiting factor for its application. In this paper, a parallelized implementation of an iterative CS reconstruction method for 3D radial acquisitions using a commercial graphics processing unit (GPU) is presented. The execution time of the GPU-implemented CS reconstruction was compared with that of the C++ implementation and the efficacy of the undersampled 3D radial acquisition with CS reconstruction was investigated in both phantom and whole-heart coronary data sets. Subsequently, the efficacy of CS in suppressing streaking artifacts in 3D whole-heart coronary MRI with 3D radial imaging and its convergence properties were studied. The CS reconstruction provides improved image quality (in terms of vessel sharpness and suppression of noise-like artifacts) compared with the conventional 3D gridding algorithm and the GPU implementation greatly reduces the execution time of CS reconstruction yielding 34–54 times speed-up compared with C++ implementation.

Advanced sulfur batteries could revolutionize the city life, including electrical vehicles and grid systems. In article number https://doi.org/10.1002/adfm.201707411, Chong Rae Park, Seung Jae Yang, and co‐workers revisit the literature on functional interlayers and separators for lithium‐sulfur batteries. The trade‐off relationships of PS‐, e‐, and k‐functions are outlined and design rules for balancing these three functions are presented.

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