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Aqueous zinc‐ion batteries (ZIBs) have shown great potential in the fields of wearable devices, consumer electronics, and electric vehicles due to their high level of safety, low cost, and multiple electron transfer. The layered cathode materials of ZIBs hold a stable structure during charge and discharge reactions owing to the ultrafast and straightforward (de)intercalation‐type storage mechanism of Zn2+ ions in their tunable interlayer spacing and their abilities to accommodate other guest ions or molecules. Nevertheless, the challenges of inadequate energy density, dissolution of active materials, uncontrollable byproducts, increased internal pressure, and a large de‐solvation penalty have been deemed an obstacle to the development of ZIBs. In this review, recent strategies on the structure regulation of layered materials for aqueous zinc‐ion energy storage devices are systematically summarized. Finally, critical science challenges and future outlooks are proposed to guide and promote the development of advanced cathode materials for ZIBs. [ABSTRACT FROM AUTHOR]

The electronic and optical properties of graphene are greatly dependent on the the number of layers. For the precise control of the graphene layers, atomic layer etching (ALE), a cyclic etching method achieved through chemical adsorption and physical desorption, can be the most powerful technique due to barely no damage and no contamination. In this study, we demonstrated the ALE process of graphene layers without noticeably damaging the graphene by using a controlled low energy oxygen (O2+/O+)-ion for chemical adsorption and a low energy Ar+-ion (11.2 eV) for physical desorption. In addition, using a trilayer graphene, mono- and bi-layer graphene could be successfully fabricated after one- and two-cycle ALE of the trilayer graphene, respectively. We believe that the ALE technique presented herein can be applicable to all layered materials such as graphene, black phosphorous and transition metal dichalcogenides which are important for next generation electronic devices.

It is still a challenge to develop electrocatalyst for the efficient adsorption and conversion of organic molecule in aqueous media. Herein, a hetero‐interface structure based on CuO@Ni(OH)2 is rationally designed to enhance the performance of benzyl alcohol oxidation to benzoic acid. A high Faradaic efficiency of 99% and the yield of 3.09 mmol cm−2 h−1 are achieved at 1.70 V versus reversible hydrogen electrode, outperforming the previously reported electrocatalysts. Furthermore, a membrane‐free flow electrolyzer was assembled based on CuO@Ni(OH)2 hetero‐interface, exhibiting a much high yielding of benzoic acid (6.73 mmol cm−2 h−1) and hydrogen (0.35 L cm−2 h−1) with excellent stability. Both experimental data and density functional theory calculations verify that the electron is tend to accumulate at the hetero‐interface, thus accelerating the adsorption of reactant and intermediate and reducing the energy barrier of the conversion of benzyl alcohol to benzoic acid. [ABSTRACT FROM AUTHOR]

While microplastic analysis in aquatic systems is rather well standardized, the determination of microplastics in terrestrial samples has been less explored. Here, we review methods for microplastic analysis, with focus on sampling location and design, soil quantity, sampling depth and equipment, and sample handling and preservation. We found that the random sampling design can be used to collect a representative sample. Stainless steel shovels or soil augers were the most common tools for collecting topsoil, from 0 to 30 cm. Deep soil samples, of more than 100 cm depth, can only be obtained using a core drill. The number of soil samples collected in the field depends on the available budget and instruments for microplastic analysis. For example, if a micro-Fourier transform infrared microscope is used for analysis, soil samples as small as 15.0 g per point can be collected. Once the soils are collected, they can be stored in non-plastic containers, e.g., aluminum bags, to reduce contamination. [ABSTRACT FROM AUTHOR]