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Aqueous rechargeable zinc-ion batteries (ZIBs) are attractive candidates for application in energy storage technology. However, the formation of Zn dendrites at a potential close to the Zn/Zn2+ redox potential can severely limit battery rechargeability and energy density. Herein, hexagonal MoO3 (h-MoO3) is proposed as an intercalation anode (discharge potential of 0.36 V (vs. Zn2+/Zn)) as a potential replacement for Zn metal plates for the first time and it showed a specific capacity of 120 mA h g−1 at 0.2 A g−1 with superior cycling stability. Furthermore, a zinc metal-free full cell was successfully demonstrated with this h-MoO3 anode and a Zn0.2MnO2 cathode. The cell delivered a specific capacity of 56.7 mA h g−1 which corresponds to an energy density of 61 W h kg−1 (based on the total mass of anode and cathode materials), higher than that of most aqueous zinc ion batteries. Furthermore, excellent cycling life was recorded as the full ZIB cell achieved ca. 100% of its original capacity after 1000 cycles. Based on the preliminary investigation of utilizing h-MoO3 as the ZIB anode, the results have shown significant promise in achieving Zn ion full batteries for energy storage applications. [ABSTRACT FROM AUTHOR]

Differentially expressed miRNAs in the GEO profile of ischemic stroke were analyzed to clarify the specific role of microRNA-324-5p (miRNA-324-5p) in ischemic stroke and the potential mechanism. After screening out miRNA-324-5p, its level in peripheral blood of stroke patients and in vitro oxygen-glucose deprivation (OGD)-induced primary rat neurons was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Regulatory effects of miRNA-324-5p on viability, and apoptosis of OGD-induced neurons were evaluated by CCK-8 and Annexin V fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining, respectively. Glucose uptake and caspase-3 activity in OGD-induced neurons transfected with miRNA-324-5p mimics or inhibitor were also examined. The binding of miRNA-324-5p to its target gene RAN was analyzed by dual-luciferase reporter gene assay and western blot analysis. By analyzing the data of GSE46266 profile, miRNA-324-5p expression was shown markedly lower in MCAO rats relative to controls. Identically, we also observed the downregulated miRNA-324-5p in peripheral blood of stroke patients and in vitro OGD-induced primary neurons. Overexpression of miRNA-324-5p accelerated viability, induced apoptosis and strengthened glucose uptake ability of OGD-induced neurons. Knockdown of miRNA-324-5p, conversely, obtained the opposite results. Furthermore, we confirmed the binding of miRNA-324-5p to RAN, the target gene that was negatively regulated by miRNA-324-5p. Importantly, RAN overexpression partially reversed the regulatory effect of miRNA-324-5p on viability and glucose uptake of OGD-induced neurons. miRNA-324-5p is downregulated after ischemic stroke, which aggravates the disease condition by inhibiting neuronal proliferation and glucose uptake via upregulating RAN. [ABSTRACT FROM AUTHOR]

Highlights: Bi2S3 is proposed as a promising cathode material for rechargeable aqueous Zn ion battery. The Zn/Bi2S3 battery shows a reversible capacity of 161 mAh g−1 at 0.2 A g−1 and good cyclic stability of up to 100 cycles with ca. 100% retention. The storage mechanism in the Bi2S3 cathode is related to the reversible Zn ion intercalation/extraction reactions and the capacitive contribution. Aqueous Zn ion batteries (ZIBs) are promising in energy storage due to the low cost, high safety, and material abundance. The development of metal oxides as the cathode for ZIBs is limited by the strong electrostatic forces between O2− and Zn2+ which leads to poor cyclic stability. Herein, Bi2S3 is proposed as a promising cathode material for rechargeable aqueous ZIBs. Improved cyclic stability and fast diffusion of Zn2+ is observed. Also, the layered structure of Bi2S3 with the weak van der Waals interaction between layers offers paths for diffusion and occupancy of Zn2+. As a result, the Zn/Bi2S3 battery delivers high capacity of 161 mAh g−1 at 0.2 A g−1 and good cycling stability up to 100 cycles with ca. 100% retention. The battery also demonstrates good cyclic performance of ca. 80.3% over 2000 cycles at 1 A g−1. The storage mechanism in the Bi2S3 cathode is related to the reversible Zn ion intercalation/extraction reactions and the capacitive contribution. This work indicates that Bi2S3 shows great potential as the cathode of ZIBs with good performance and stability. [ABSTRACT FROM AUTHOR]

Self-assembly of subnanometer (sub-1 nm) scale polyhedral building blocks can yield some superstructures with novel and interesting morphology as well as potential functionalities. However, achieving the self-assembly of sub-1 nm polyhedral building blocks is still a great challenge. Herein, through encapsulating the titanium-substituted polyoxometalate (POM, K 7 PTi 2 W 10 O 40 ) with tetrabutylammonium cations (TBA + ), we first synthesized a sub-1 nm rhombic dodecahedral building block by further tailoring the spatial distribution of TBA + on the POM. Molecular dynamics (MD) simulations demonstrated the eight TBA + cations interacted with the POM cluster and formed the sub-1 nm rhombic dodecahedron. As a result of anisotropy, the sub-1 nm building blocks have self-assembled into rhombic dodecahedral POM (RD-POM) assemblies at the microscale. Benefiting from the regular structure, Br - ions, and abundant active sites, the obtained RD-POM assemblies exhibit excellent catalytic performance in the cycloaddition of CO 2 with epoxides without co-catalysts. This work provides a promising approach to tailor the symmetry and structure of sub-1 nm building blocks by tuning the spatial distribution of ligands, which may shed light on the fabrication of superstructures with novel properties by self-assembly., (© 2023 Wiley-VCH GmbH.)

Tandem catalysis provides an economical and energy-efficient process for the production of fine chemicals. In this work, we demonstrate that a rationally synthesized carbon-based catalyst with atomically dispersed dual Fe-Al sites (ADD-Fe-Al) achieves superior catalytic activity for the one-pot oxidative carboxylation of olefins (conversion ∼97%, selectivity ∼91%), where the yield of target product over ADD-Fe-Al is at least 62% higher than that of monometallic counterparts. The kinetic results reveal that the excellent catalytic performance arises from the synergistic effect between Fe (oxidation site) and Al sites (cycloaddition site), where the efficient CO 2 cycloaddition with epoxides in the presence of Al sites (3.91 wt %) positively shifts the oxidation equilibrium to olefin epoxidation over Fe sites (0.89 wt %). This work not only offers an advanced catalyst for oxidative carboxylation of olefins but also opens up an avenue for the rational design of multifunctional catalysts for tandem catalytic reactions in the future.

Zn dendrite growth during repeated plating and stripping of a Zn metal anode often causes short-circuiting by puncturing the separator. Herein, we propose a separator modification strategy to regulate the Zn-ion flux and achieve uniform Zn deposition through the OH-terminated SiO 2 nanosphere coating. The interspaces between the uniform SiO 2 nanospheres construct a network of Zn-ion transport channels, and the negatively charged hydroxyl groups on the surface of SiO 2 nanospheres can electrostatically attract the Zn ions to direct the ion migration. The negative charges on SiO 2 nanospheres are retained at a higher pH, which enables the SiO 2 coating to consistently regulate the Zn-ion flux in the operating pH range of the Zn stripping/plating process. With a uniform Zn deposition guided by the SiO 2 coating, the dendrite formation is suppressed and the side reactions are alleviated. As a result, the Zn||Zn symmetric cell achieves a cyclic life of 1000 h at both 3 and 5 mA cm -2 . Meanwhile, the Zn||Cu asymmetric cell is able to maintain a Coulombic efficiency of 99.62% at 1 mA cm -2 for 2000 cycles, which outperforms many previously reported strategies.

Aqueous Zn ion batteries (ZIBs) are promising in energy storage due to the low cost, high safety, and material abundance. The development of metal oxides as the cathode for ZIBs is limited by the strong electrostatic forces between O 2- and Zn 2+ which leads to poor cyclic stability. Herein, Bi 2 S 3 is proposed as a promising cathode material for rechargeable aqueous ZIBs. Improved cyclic stability and fast diffusion of Zn 2+ is observed. Also, the layered structure of Bi 2 S 3 with the weak van der Waals interaction between layers offers paths for diffusion and occupancy of Zn 2+ . As a result, the Zn/Bi 2 S 3 battery delivers high capacity of 161 mAh g -1 at 0.2 A g -1 and good cycling stability up to 100 cycles with ca. 100% retention. The battery also demonstrates good cyclic performance of ca. 80.3% over 2000 cycles at 1 A g -1 . The storage mechanism in the Bi 2 S 3 cathode is related to the reversible Zn ion intercalation/extraction reactions and the capacitive contribution. This work indicates that Bi 2 S 3 shows great potential as the cathode of ZIBs with good performance and stability.

Organic compounds, such as polyvinylidene fluoride (PVDF), have been widely used as a binder in battery electrode preparations. While such an approach does not have a significant impact on the performance of the batteries that utilize low valence ions, such as the Li ion battery (LIB), the diffusion of high valence ions (such as Zn 2+ ) will be severely impaired. This will be especially pronounced if the polymeric binder contains highly electronegative atoms, such as fluorine. The high charge density ions, such as Zn 2+ , tend to adsorb onto these electronegative atoms, thus the mobility of these ions across the material is inevitably affected. As such, it becomes highly necessary to consider the binder-free electrode architecture when designing a high rate performing and cycling-stable zinc ion battery (ZIB) cathode. Herein, this work demonstrates an improved Zn ion battery by adopting a freestanding electrode. The obtained V 2 O 5 /CNT paper electrode delivers a specific capacity of 312 mA h g -1 , while achieving a respectable 75% retention in capacity after increasing the current density by 10-fold. Furthermore, excellent cycling stability is recorded with 81% capacity retention after 2000 cycles at 1.0 A g -1 . Thus, this work clearly demonstrated that the freestanding electrode is a promising approach for high valence ion batteries.