Here, we report that transition-metal dichalcogenides such as MoS2 and WS2 can be decorated with gold nanoparticles by a spontaneous redox reaction with hexachloroauric acid in water. The resulting gold nanoparticles tend to grow at defective sites, and therefore, selective decorations at the edges and the line defects in the basal planes of bulk single crystals were observed. The lithium intercalation-exfoliation process makes the basal planes of chemically exfoliated MoS2 and WS2 sheets much more defective than their single-crystalline counterparts, leading to a more uniform and higher-density deposition of gold nanoparticles. Due to the greatly improved charge transport between adjacent sheets, the resulting MoS2/Au and WS2/Au hybrids show significantly enhanced electrocatalytic performance toward hydrogen evolution reactions.

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Li/graphite coin cells containing different amounts of vinylene carbonate (VC) electrolyte additive were examined at different temperatures using the High Precision Charger at Dalhousie University. The charge endpoint capacities as well as the coulombic efficiency (CE) were compared to characterize the effect of the VC additive on the graphite electrode. The experiments show that VC improves the coulombic efficiency and reduces charge and discharge endpoint slippage at 50 and 60 • C. However, the addition of VC has little evident effect on the performance of the graphite electrode at 30 and 40 • C and also increases the irreversible capacity. By contrast, additions of VC have a marked impact on the coulombic efficiency and slippages of NMC positive electrodes, even at 30 • C.The next generation of lithium ion batteries (LIBs) for electric vehicles and grid energy applications requires longer cycle life and longer calendar life than LIBs for computer and phone applications. Electrolyte additives can be selected and used to improve the lifetime of LIBs. 1,2 Vinylene carbonate (VC) is one of the most studied electrolyte additives. 3-6 Aurbach et al. studied the effect of VC on the graphite electrode in Li/graphite half cells and found that VC can improve the capacity retention especially at elevated temperatures. This is because VC is reduced at higher potentials than the major solvent components and is thought to form flexible and cohesive polymeric surface products that serve as a better SEI. Aurbach et al. also found that VC did not have a pronounced impact on Li/LiMnO 4 and Li/LiNiO 2 half cells although it can also react with these positive electrode materials to make an SEI. 3 Ota el al. analyzed the impact of VC on the SEI on the graphite electrode and stated that VC has a major impact on the negative electrode and could also have some effect on the positive electrode. 4, 5 Recently, Ouatuni et al. stated that VC can react with both the negative and positive electrode materials through a radical polymerization mechanism. 6 Our research found that VC had a more significant effect on the positive electrode, by reducing the rate of electrolyte oxidation, than on the negative electrode. 7,8 Here, the impact of VC on the coulombic efficiency and charge endpoint slippage of Li/graphite half cells is studied using the High Precision Charger at Dalhousie University. 9 Li/graphite cells with different electrode formulations and different amounts of VC additive were tested at temperatures between 30 and 60 • C.

MoSx is grown on crumpled graphene particles supported on carbon cloth substrates for the hydrogen evolution reaction. Modifying carbon cloth with crumpled graphene allows for higher loading levels of MoSx and thus significantly enhances its electrocatalytic activity. Measurements yield a current density of –220 mA cm−2 at an overpotential of 0.3 V (before iR correction) for the crumpled‐graphene‐modified carbon cloth.

Quasi-random nanostructures have attracted significant interests for photon management purposes. To optimize such patterns, typically very expensive fabrication processes are needed to create the pre-designed, subwavelength nanostructures. While quasi-random photonic nanostructures are abundant in nature (for example, in structural coloration), interestingly, they also exist in Blu-ray movie discs, an already mass-produced consumer product. Here we uncover that Blu-ray disc patterns are surprisingly well suited for light-trapping applications. While the algorithms in the Blu-ray industrial standard were developed with the intention of optimizing data compression and error tolerance, they have also created quasi-random arrangement of islands and pits on the final media discs that are nearly optimized for photon management over the solar spectrum, regardless of the information stored on the discs. As a proof-of-concept, imprinting polymer solar cells with the Blu-ray patterns indeed increases their efficiencies. Simulation suggests that Blu-ray patterns could be broadly applied for solar cells made of other materials.