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Silicon, which has been widely studied by virtue of its extremely high theoretical capacity and abundance, is recognized as one of the most promising anode materials for the next generation of lithium‐ion batteries. However, silicon undergoes tremendous volume change during cycling, which leads to the destruction of the electrode structure and irreversible capacity loss, so the promotion of silicon materials in commercial applications is greatly hampered. In recent years, many strategies have been proposed to address these shortcomings of silicon. This Review focused on different coatings materials (e. g., carbon‐based materials, metals, oxides, conducting polymers, etc.) for silicon materials. The role of different types of materials in the modification of silicon‐based material encapsulation structure was reviewed to confirm the feasibility of the protective layer strategy. Finally, the future research direction of the silicon‐based material coating structure design for the next‐generation lithium‐ion battery was summarized.

High‐entropy oxides (HEOs) are gradually becoming a new focus for lithium‐ion battery (LIB) anodes due to their vast element space/adjustable electrochemical properties and unique single‐phase retention ability. However, the sluggish kinetics upon long cycling limits their further generalization. Here, oxygen vacancies with targeted functionality are introduced into rock salt‐type (MgCoNiCuZn)O through a wet‐chemical molten salt strategy to accelerate the ion/electron transmission. Both experimental results and theoretical calculations reveal the potential improvement of lithium storage, charge transfer, and diffusion kinetics from HEO surface defects, which ultimately leads to enhanced electrochemical properties. The currently raised strategy offers a modular approach and enlightening insights for defect‐induced HEO‐based anodes.

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An efficient adsorbent (a quaternary ammonium salt-modified chitosan microsphere, CTA-CSM) was synthesized via an emulsion cross-linking reaction between 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CTA) and chitosan (CS). The adsorption efficiency of the CTA-CSM as an adsorbent was studied using methyl orange dye to evaluate its suitability for wastewater purification. The characterization results showed that the CTA groups were successfully grafted onto the CS microspheres, and the as-prepared CTA-CSM samples exhibited a smooth surface and good dispersibility. The modification of CTA on CTA-CSM significantly improved its ability to remove methyl orange dye. The adsorption process of methyl orange by CTA-CSM was well described by the Langmuir isotherm model and followed the pseudo-second-order kinetic model. Under the optimal conditions, the maximum removal rate (98.9%) and adsorption capacity (131.9 mg/g) of CTA-CSM was higher than those of other previous reports; its removal rate for methyl orange was still up to 87.4% after five recycles. Hence, CTA-CSM is a very promising material for practical dyeing wastewater purification.

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