Lithium-sulfur batteries have high promise for application in next-generation energy storage. However, further advances have been hindered by various intractable challenges, particularly three notorious problems: the “shuttle effect”, sluggish kinetics...

Rapid fabrication of flexible electronics is attracting much attention in many industries. There is a need for rapidly producing flexible electronic components without the reliance on costly precursor materials and complex processes. In this work, a direct laser writing process is presented as capable of rapidly depositing flexible copper or copper oxide structures with a high degree of control over electrical properties. The direct laser writing process uses a low-power fiber laser beam to selectively irradiate a thin film of copper ions to form and interconnect copper nanoparticles. The electrical properties of the deposited patterns can be controlled through tuning laser power, scanning speed, and beam defocus. The microstructures of patterns printed at varying laser powers are investigated using SEM, XPS, and XRD and the relation between laser power and sheet resistance is explored. The results showed that high laser energy densities resulted in highly conductive patterns of metallic copper, whereas lower energy patterns resulted in copper oxide rich patterns with significantly lower conductivity. This method can produce high-quality flexible electronic components with a range of potential applications, as demonstrated by the proof-of-concept fabrication of a flexible memristive junction with resistive switching observed at +/- 0.7V, and a Ron/Roff ratio of 10^2.

The high demand for thin, lightweight yet fast and efficient devices is a driving force behind the miniaturization trend in the electronics industry. Specifically, the advancement of semiconducting single-walled carbon nanotubes (SWNTs) can continue to revolutionize transistors, although there are still many challenges ahead. We have previously reported an alignment relay technique (ART) that is capable of simultaneously controlling the alignment, length, and diameter of surface deposited SWNTs. However, the current technique yields inconsistencies in orientation, lengths of tubes, and their density. Here, we present a reviewed ART protocol that includes sonication for improved selectivity. We show that the SWNTs average alignment increased from 40% to 77% within a 10°range in orientation with sonication times as low as 5 min. Sonication generated larger diameter nanotubes on the surface, with a preference for semiconducting chiral tubes in the range of 1.44−1.61 nm in diameter. Consequently, simple alterations to the standard alignment relay technique can prove to be prosperous in improving selectivity and orientational control of single-walled carbon nanotubes. This work has direct impact for the simultaneous control of nanotube alignment and nanotube chiralities.

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Sulfenyl chlorides are a reliable starting material to access allenyl sulfoxides with aryl or haloalkyl groups by way of sulfenate ester formation followed by [2,3]-sigmatropic rearrangement. Application of the chemistry of alkanesulfenyl chlorides is much less common due to competing fates along the reaction pathway. In this paper, N-sulfanylsuccimides (thiosuccinimides) are shown to be a viable replacement for sulfenyl chlorides. A number of allenyl alkyl sulfoxides are prepared in fair to good yields (21-73 %, 21 examples). In addition, some butyn-1,4-diols can be selectively monofunctionalized to form allenyl sulfoxides (26-71 %) with a hydroxyalkyl group geminal to the sulfur. Butynediols also permit synthetic access to dienes via successive sulfenate ester formation and [2,3]-sigmatropic rearrangement reactions. N-2-Trimethylsilylethylthosucinimides were among the highest yielding of the thioimides.

The persistence of pharmaceuticals and personal care products (PPCPs) in water has been a cause for concern for several years. Many studies have successfully used TiO2/UV photocatalysis to remove these compounds from water. In order to optimize these systems for large-scale water treatment, the effects of the reaction matrix, methods to improve energy efficiency, and methods for easy catalyst separation must be considered. The following study examines the photocatalytic degradation of a cocktail of 18 PPCPs using a porous titanium–titanium dioxide membrane and the effect of solution pH on kinetic rate constants. The addition of methanol to the reaction—commonly used as a carrier solvent—had a significant effect on kinetic rate constants even at low concentrations. Solution pH was also found to influence kinetic rate constants. Compounds had higher kinetic rate constants when they were oppositely charged to the membrane at experimental pH as opposed to similarly charged, suggesting that electrostatic forces have a significant effect. The controlled periodic illumination of UV–LEDs was also investigated to increase photonic efficiency. The dual-frequency light cycle used did not cause a decrease in degradation for many compounds, successfully increasing the photonic efficiency without sacrificing performance.

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