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Abstract The striped flea beetle (SFB, Phyllotreta striolata) can cause serious harm to cruciferous crops in both the larval and adult stages. Presently, there are no other sustainable alternatives to the use of chemical pesticides for controlling SFB infestation. In this study, the use of a seed-pelletized coating of spinetoram effectively reduced the numbers of SFB and its feedings on the flowering cabbage seedlings, whereas, in combination with the insect-proof net, it controlled the SFB infestation throughout the cabbage growth period. The analysis of the pesticide residues in soil and different cabbage parts indicated the degradation dynamics of spinetoram. The concentration of spinetoram in cabbage parts decreased over time, while increased first and subsequently decreased in soil. Furthermore, estimation of the half-life of spinetoram revealed that via seed-palletized application spinetoram half-life was found to be 2.82 days in soil, 4.21 days in the root, 5.77 days in the stem, and 3.57 days in the leaf, respectively. Both the lower pesticide residues and the half-life of spinetoram in soil and cabbage parts suggested it to be a promising environment and food-safe pesticide in controlling SFB. Moreover, the seed-pelletized coating ensured a sustainable release of spinetoram that can reduce the pesticide application frequency and be cost-effective and pocket-friendly for the farmers.

VS2 is one of the attractive layered cathodes for alkali metal‐ion batteries. However, the understanding of the detailed reaction processes and energy storage mechanism is still inadequate. Herein, the Li+/Na+/K+ insertion/extraction mechanisms of VS2 cathode are elucidated on the basis of experimental analyses and theoretical simulations. It is found that the insertion/extraction behavior of Li+ is partially irreversible, while the insertion/extraction behavior of Na+/K+ is completely reversible. The detailed intermediates and final products (Li0.33VS2, LiVS2, Na0.5VS2, NaVS2, K0.6VS2, KzVS2, z > 0.6) during the discharging/charging processes are identified, indicating that VS2 undergoes different phase transitions and solid–solution reactions in different battery systems, which have a great influence on the battery performance. Moreover, the diffusion of Na+ in VS2 cathode is demonstrated to be much slower than that of Li+ and K+. Such mechanistic research provides a reference for in‐depth understanding of energy storage in layered transition metal sulfides/selenides. [ABSTRACT FROM AUTHOR]

Li-rich layered oxides have been in focus because of their high specific capacity. However, they usually suffer from poor kinetics, severe voltage decay, and capacity fading. Herein, a long-neglected Li-deficient method is demonstrated to address these problems by simply reducing the lithium content. Appropriate lithium vacancies can improve dynamics features and induce in situ surface spinel coating and nickel doping in the bulk. Therefore, the elaborately designed Li 1.098 Mn 0.533 Ni 0.113 Co 0.138 O 2 cathode possesses improved initial Coulombic efficiency, excellent rate capability, largely suppressed voltage decay, and outstanding long-term cycling stability. Specifically, it shows a superior capacity retention of 93.1% after 500 cycles at 1 C (250 mA g -1 ) with respect to the initial discharge capacity (193.9 mA h g -1 ), and the average voltage still exceeds 3.1 V. In addition, the discharge capacity at 10 C can be as high as 132.9 mA h g -1 . More importantly, a Li-deficient cathode can also serve as a prototype for further performance enhancement, as there are plenty of vacancies.

The development of manganese dioxide as the cathode for aqueous Zn-ion battery (ZIB) is limited by the rapid capacity fading and material dissolution. Here, a highly reversible aqueous ZIB using graphene scroll-coated α-MnO 2 as the cathode is proposed. The graphene scroll is uniformly coated on the MnO 2 nanowire with an average width of 5 nm, which increases the electrical conductivity of the MnO 2 nanowire and relieves the dissolution of the cathode material during cycling. An energy density of 406.6 Wh kg -1 (382.2 mA h g -1 ) at 0.3 A g -1 can be reached, which is the highest specific energy value among all the cathode materials for aqueous Zn-ion battery so far, and good long-term cycling stability with 94% capacity retention after 3000 cycles at 3 A g -1 are achieved. Meanwhile, a two-step intercalation mechanism that Zn ions first insert into the layers and then the tunnels of MnO 2 framework is proved by in situ X-ray diffraction, galvanostatic intermittent titration technique, and X-ray photoelectron spectroscopy characterizations. The graphene scroll-coated metallic oxide strategy can also bring intensive interests for other energy storage systems., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)