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Cellulose, as the most abundant natural polymer on Earth, has long captured researchers' attention due to its high strength and modulus. Nevertheless, transferring its exceptional mechanical properties to macroscopic 2D and 3D materials poses numerous challenges. This review provides an overview of the research progress in the development of strong cellulose-based materials using both the "bottom-up" and "top-down" approaches. In the "bottom-up" strategy, various forms of regenerated cellulose-based materials and nanocellulose-based high-strength materials assembled by different methods are discussed. Under the "top-down" approach, the focus is on the development of reinforced cellulose-based materials derived from wood, bamboo, rattan and straw. Furthermore, a brief overview of the potential applications fordifferent types of strong cellulose-based materials is given, followed by a concise discussion on future directions. [ABSTRACT FROM AUTHOR]

The adjustable structures and remarkable physicochemical properties of 2D monoelemental materials, such as silicene and germanene, have attracted significant attention in recent years. They can be transformed into silicane (SiH) and germanane (GeH) through covalent functionalization via hydrogen atom termination. However, synthesizing these materials with a scalable and low‐cost fabrication process to achieve high‐quality 2D SiH and GeH poses challenges. Herein, groundbreaking 2D SiH and GeH materials with varying compositions, specifically Si0.25Ge0.75H, Si0.50Ge0.50H, and Si0.75Ge0.25H, are prepared through a simple and efficient chemical exfoliation of their Zintl phases. These 2D materials offer significant advantages, including their large surface area, high mechanical flexibility, rapid electron mobility, and defect‐rich loose‐layered structures. Among these compositions, the Si0.50Ge0.50H electrode demonstrates the highest discharge capacity, reaching up to 1059 mAh g−1 after 60 cycles at a current density of 75 mA g−1. A comprehensive ex‐situ electrochemical analysis is conducted to investigate the reaction mechanisms of lithiation/delithiation in Si0.50Ge0.50H. Subsequently, an initial assessment of the c‐Li15(SixGe1‐x)4 phase after lithiation and the a‐Si0.50Ge0.50 phase after delithiation is presented. Hence, this study contributes crucial insights into the (de)lithiation reaction mechanisms within germanane‐silicane alloys. Such understanding is pivotal for mastering promising materials that amalgamate the finest properties of silicon and germanium. [ABSTRACT FROM AUTHOR]

Crystalline γ‐Ga2O3@rGO core–shell nanostructures are synthesized in gram scale, which are accomplished by a facile sonochemical strategy under ambient condition. They are composed of uniform γ‐Ga2O3 nanospheres encapsulated by reduced graphene oxide (rGO) nanolayers, and their formation is mainly attributed to the existed opposite zeta potential between the Ga2O3 and rGO. The as‐constructed lithium‐ion batteries (LIBs) based on as‐fabricated γ‐Ga2O3@rGO nanostructures deliver an initial discharge capacity of 1000 mAh g−1 at 100 mA g−1 and reversible capacity of 600 mAh g−1 under 500 mA g−1 after 1000 cycles, respectively, which are remarkably higher than those of pristine γ‐Ga2O3 with a much reduced lifetime of 100 cycles and much lower capacity. Ex situ XRD and XPS analyses demonstrate that the reversible LIBs storage is dominant by a conversion reaction and alloying mechanism, where the discharged product of liquid metal Ga exhibits self‐healing ability, thus preventing the destroy of electrodes. Additionally, the rGO shell could act robustly as conductive network of the electrode for significantly improved conductivity, endowing the efficient Li storage behaviors. This work might provide some insight on mass production of advanced electrode materials under mild condition for energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

Degradation and reprocessing of thermoset polymers have long been intractable challenges to meet a sustainable future. Star strategies via dynamic cross‐linking hydrogen bonds and/or covalent bonds can afford reprocessable thermosets, but often at the cost of properties or even their functions. Herein, a simple strategy coined as hyperbranched dynamic crosslinking networks (HDCNs) toward in‐practice engineering a petroleum‐based epoxy thermoset into degradable, reconfigurable, and multifunctional vitrimer is provided. The special characteristics of HDCNs involve spatially topological crosslinks for solvent adaption and multi‐dynamic linkages for reversible behaviors. The resulting vitrimer displays mild room‐temperature degradation to dimethylacetamide and can realize the cycling of carbon fiber and epoxy powder from composite. Besides, they have supra toughness and high flexural modulus, high transparency as well as fire‐retardancy surpassing their original thermoset. Notably, it is noted in a chance‐following that ethanol molecule can induce the reconstruction of vitrimer network by ester‐exchange, converting a stiff vitrimer into elastomeric feature, and such material records an ultrahigh modulus (5.45 GPa) at −150 °C for their ultralow‐temperature condition uses. This is shaping up to be a potentially sustainable advanced material to address the post‐consumer thermoset waste, and also provide a newly crosslinked mode for the designs of high‐performance polymer. [ABSTRACT FROM AUTHOR]

Lithium‐rich layered oxides (LLOs) are promising candidate cathode materials for safe and inexpensive high‐energy‐density Li‐ion batteries. However, oxygen dimers are formed from the cathode material through oxygen redox activity, which can result in morphological changes and structural transitions that cause performance deterioration and safety concerns. Herein, a flake‐like LLO is prepared and aberration‐corrected scanning transmission electron microscopy (STEM), in situ high‐temperature X‐ray diffraction (HT‐XRD), and soft X‐ray absorption spectrum (sXAS) are used to explore its crystal facet degradation behavior in terms of both thermal and electrochemical processes. Void‐induced degradation behavior of LLO in different facet reveals significant anisotropy at high voltage. Particle degradation originates from side facets, such as the (010) facet, while the close (003) facet is stable. These results are further understood through ab initio molecular dynamics calculations, which show that oxygen atoms are lost from the {010} facets. Therefore, the facet degradation process is that oxygen molecular formed in the interlayer and accumulated in the ab plane during heating, which result in crevice‐voids in the ab plane facets. The study reveals important aspects of the mechanism responsible for oxygen ‐anionic activity‐based degradation of LLO cathode materials used in lithium‐ion batteries. In particular, this study provides insight that enables precise and efficient measures to be taken to improve the thermal and electrochemical stability of an LLO. [ABSTRACT FROM AUTHOR]