Typically, the constant consumption of conventional fossil fuels leads to over-emission of carbon dioxide (CO 2 ) and accelerates the trend of global warming. [2] Therefore, in recent years, researchers from both academia and industry have devoted tremendous efforts to developing new energy systems to reduce CO 2 emission as well as converting CO 2 into valuable chemicals. [3] Among all explored systems for CO 2 reduction, the idea of rechargeable metal-CO 2 batteries exhibits significant promise for effective CO 2 reduction, value-added CO 2 conversion, as well as high-performance energy storage. It is therefore considered a "kill two birds with one stone" strategy and becomes a new research hotspot in areas of both CO 2 reduction and electrochemical energy storage. [3j,4] The first article of a primary Li-CO 2 battery with a nonaqueous electrolyte was reported in 2013. [5] Since then, diverse rechargeable metal-CO 2 batteries using different alkali metal anodes (Li, Na, K) have been constructed and systematically analyzed in the past few years. [6] However, the alkali metals possess high reaction activities, [6g,7] and Li, Na, and K anodes all suffer from dendrite formation during cycling that leads to severe battery safety issues, reduces battery cycle life, and restricts their practical applications. It is urgent to explore new metal anodes for metal-CO 2 batteries with comparatively lower activities and meanwhile being dendrite-free. [8] With that in mind, magnesium metal could be a promising option. On the one hand, Mg possesses a high theoretical volumetric capacity of 3833 mAh cm −3 (vs 2062 mAh cm −3 for Li, 1128 mAh cm −3 for Na, and 591 mAh cm −3 for K), [9] enabling Mg to fix more CO 2 per unit volume. On the other hand, Mg storage in the Earth's crust is abundant (about 2.9%), which is about 1500 times compared to Li (0.002%), resulting in a theoretically significantly lower production cost of Mg batteries. Most importantly, Mg metal anode's dendrite-free nature is favorable for battery safety and long cycle stability. [10] As the rechargeable Mg-CO 2 battery processes the above advantages of high volumetric energy density, high safety, environmental friendliness, and low cost, it is envisaged as a promising strategy for excellent energy storage and effective CO 2 exploitations. [9c] In spite of the favorable factors, there are very few reports in the literature related to Mg-CO 2 batteries with nonaqueous

Composite materials with ordered microstructures often lead to enhanced functionalities that a single material can hardly achieve. Many biomaterials with unusual microstructures can be found in nature; among them, many possess anisotropic and even directional physical and chemical properties. With inspiration from nature, artificial composite materials can be rationally designed to achieve this anisotropic behavior with desired properties. Here, a metallic wood with metal continuously filling the wood vessels is developed, which demonstrates excellent anisotropic electrical, thermal, and mechanical properties. The well-aligned metal rods are confined and separated by the wood vessels, which deliver directional electron transport parallel to the alignment direction. Thus, the novel metallic wood composite boasts an extraordinary anisotropic electrical conductivity (σ /σ ) in the order of 10 , and anisotropic thermal conductivity (κ /κ ) of 18. These values exceed the highest reported values in existing anisotropic composite materials. The anisotropic functionality of the metallic wood enables it to be used for thermal management applications, such as thermal insulation and thermal dissipation. The highly anisotropic metallic wood serves as an example for further anisotropic materials design; other composite materials with different biotemplates/hosts and fillers can achieve even higher anisotropic ratios, allowing them to be implemented in a variety of applications.

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Halide perovskites are revolutionizing the renewable energy sector owing to their high photovoltaic efficiency, low manufacturing cost, and flexibility. Their remarkable mobility and long carrier lifetime are also valuable for information technology, but fundamental challenges like poor stability under an electric field prevent realistic applications of halide perovskites in electronics. Here, it is discovered that valleytronics is a promising route to leverage the advantages of halide perovskites and derivatives for information storage and processing. The synthesized all‐inorganic lead‐free perovskite derivative, Cs3Bi2I9, exhibits strong light–matter interaction and parity‐dependent optically addressable valley degree of freedom. Robust optical helicity in all odd‐layer‐number crystals with inversion symmetry breaking is observed, indicating excitonic coherence extending well beyond 11 layers. The excellent optical and valley properties of Cs3Bi2I9 arise from the unique parallel bands, according to first principles calculations. This discovery points to new materials design principles for scalable valleytronic devices and demonstrates the promise of perovskite derivatives beyond energy applications.

To satisfy the increasing energy density requirements for electric vehicles and grid-scale energy storage systems, Nirich layered oxide cathode materials are often fabricated as micron-sized secondary spherical particles consisting of nanosized single crystals. Unfortunately, the hierarchical structure inevitably induces intergranular cracks and parasitic reactions at the cathode− electrolyte interphase, aggravating chemomechanical instability and seriously hindering their practical application. Here, we propose a nanowelding strategy to build consolidation points at the grain boundary of the primary particles, which dramatically enhances the capacity retention and chemomechanical stability. Meanwhile, the oxygen vacancies in the ceria-based solid electrolyte possessing oxygen adsorbing and storage capability can restrain the active oxygenates in the surficial lattice to avoid oxygen evolution. Experimental characterization further confirms that this unique architecture can effectively prevent the liquid electrolyte from penetrating into the active material along the grain boundary and consequently eliminate the adverse effects, including intergranular cracks, cathode electrolyte interface formation and growth, and the layered structure-rock salt phase irreversible transition. This finding provides a promising approach to realize the rapid commercialization of highly stabilized nickel-rich cathode materials for high-performance lithium-ion batteries.

Our study provides evidence HG regulates Nrf2-HO-1-Hmgb1 axis and attenuates intestinal IR injury in mice.

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