Biomimetic Channels Design in Metal-Organic Framework Enabling Highly Lithium-Ion Conduction for Lithium-Metal Batteries.

Solid-state electrolytes (SSEs) based on metal-organic frameworks (MOFs) are an ideal material for constructing high-performance lithium metal batteries (LMBs). However, the low ion conductivity and poor interface contact (especially at low temperatures) still seriously hinder its further application. Herein, inspired by the Na+/K+ conduction in biology systems, a series (NH2, OH, NH-(CH2)3-SO3H)-modified MIL-53-X as SSEs is reported. These functional groups are similar to anions suspended in biological ion channels, partially repelling anions while allowing cations to be effectively transported through pore channels. Subsequently, MIL-53-X with hierarchical pore structure (H-MIL-53-X) is obtained by introducing lauric acid as a regulator, and then the effects of structural design and morphology control on its performance are explored. The conductivity of H-MIL-53-NH-SO3Li with multi-level pore structure and modified by sulfonic acid groups reached 2.2 × 10-3 S cm-1 at 25 °C, lithium-ion transference number of 0.78. Besides, the H-MIL-53-NH-SO3Li still has an excellent conductivity of 10-4 S cm-1 at -40 °C. Additionally, LiFePO4/Li batteries equipped with H-MIL-53-NH-SO3Li SSEs could operate stably for over 200 cycles at 0.1 C. The strategy of combining structural and morphological design of MOFs with biomimetic ion channels opens new avenues for the design of high-performance SSEs.

Controllable Synthesis of Hollow Dodecahedral Si@C Core-Shell Structures for Ultrastable Lithium-Ion Batteries.

Silicon (Si) has attracted considerable attention as a promising alternative to graphite in lithium-ion batteries (LIBs) because of its high theoretical capacity and voltage. However, the durability and cycling stability of Si-based composites have emerged as major obstacles to their widespread adoption as LIBs anode materials. To tackle these challenges, a hollow core-shell dodecahedra structure of a Si-based composite (HD-Si@C) is developed through a novel double-layer in situ growth approach. This innovative design ensures that the nano-sized Si particles are evenly distributed within a hollow carbon shell, effectively addressing issues like Si fragmentation, volume expansion, and detachment from the carbon layer during cycles. The HD-Si@C composite demonstrates remarkable structural integrity as a LIBs anode, resulting in exceptional electrochemical performance and promising practical applications, as evidenced by tests in pouch-type full cells. Notably, the composite shows outstanding cycling stability, retaining 85% of its initial capacity (713 mAh g-1) even after 3000 cycles at a high current rate of 5000 mA g-1. Additionally, the material achieves a gravimetric energy density of 369 W h kg-1, showcasing its potential for efficient energy storage solutions. This research signifies a significant step toward realizing the practical utilization of Si-based materials in the next generation of LIBs.

Upgrading Structural Conjugation in Three-Dimensional Ni-Based Metal-Organic Frameworks for Promoting Electrical Conductivity and Specific Capacitance.

Metal-organic frameworks (MOFs) have emerged as promising candidates for electrochemical energy storage and conversion due to their high specific surface areas, abundant active sites, and excellent chemical and structural tunability. However, the direct utilization of MOFs as electrochemical materials is a challenge because of the poor electroconductivity induced by the insulating nature of most organic linkers. Herein, a conjugated three-dimensional Ni-MOF {Ni(HBTC)(BPE)}n (Ni-BPE) with a 2-fold interpenetrating structure was developed via the coordination polymerization of Ni2+, a H3BTC ligand (1,3,5-benzenetricarboxylic acid), and a vinyl-functionalized bipyridine linker (1,2-di(4-pyridyl)ethylene, BPE). Ni-BPE displayed an enhanced conjugation system compared to analogous and insulated Ni-BPY that is constructed by the Ni-BTC layer and ordinary bipyridine linker (4,4'-bipyridine, BPY). Notably, upgrading structural conjugation promoted a dramatical ∼204 times increase in the electroconductivity of Ni-BPE compared to Ni-BPY. More importantly, Ni-BPE displayed a higher specific capacitance of 633.2 F g-1 (316.6 C g-1) at 1 A g-1, which exhibited a significant ∼1.5-fold enhancement than Ni-BPY. Furthermore, the asymmetric supercapacitor can reach a good energy density of 25.2 Wh kg-1 with a reasonable cycle stability of 71.0% over 5000 cycles. This work provides an effective method for optimizing the structure of insulating MOFs to enhance the electroconductivity and specific capacitance.

Fabrication of flower-like CoFe/C composites derived from ferrocene-based metal-organic frameworks: an in situ growth strategy toward high-efficiency electromagnetic wave absorption.

Magnetic/dielectric composites can achieve high-efficiency electromagnetic wave (EMW) absorption performance by integrating multiple mechanisms such as dielectric loss and magnetic loss. The bimetallic metal-organic frameworks (MOFs) assembled from ferrocene (Fc) derivative-based bridging ligands are considered ideal precursors for the preparation of magnetic/dielectric composites due to tailored alloy components with magnetic losses. Herein, a novel CoFe/C composite with nanoflower structures is successfully obtained via an in situ growth strategy to decompose an Fc-based bimetallic MOF assembled from 1,1'-ferrocene dicarboxylic acid as bridging ligands and Co2+ ions. Notably, the nanoflower structures of the obtained composites provide an effective path for the scattering and reflection of the EMW, thereby improving the impedance matching by combining dielectric and magnetic loss. The CoFe/C composite exhibits excellent EMW absorption performance and has a minimum reflection loss of -61.6 dB at 3.7 mm and an effective absorption bandwidth of 6.24 GHz at a corresponding thickness of 2.2 mm. Moreover, the obtained composite exhibits lightweight characteristics and a low radar cross-section. This work presents a novel method through Fc-based bimetallic MOF derivatives to design and develop novel magnetic/dielectric composites with efficient EMW absorption properties for comprehensive applications.

Controllable preparation of carbon coating Ge nanospheres with a cubic hollow structure for high-performance lithium ion batteries.

Germanium based nanomaterials are very promising as the anodes for the lithium ion batteries since their large specific capacity, excellent lithium diffusivity and high conductivity. However, their controllable preparation is still very difficult to achieve. Herein, we facilely prepare a unique carbon coating Ge nanospheres with a cubic hollow structure (Ge@C) via a hydrothermal synthesis and subsequent pyrolysis using low-cost GeO2 as precursors. The hollow Ge@C nanostructure not only provides abundant interior space to alleviate the huge volumetric expansion of Ge upon lithiation, but also facilitates the transmission of lithium ions and electrons. Moreover, experiment analyses and density functional theory (DFT) calculations unveil the excellent lithium adsorption ability, high exchange current density, low activation energy for lithium diffusion of the hollow Ge@C electrode, thus exhibiting significant lithium storage advantages with a large charge capacity (1483 mAh/g under 200 mA g-1), distinguished rate ability (710 mAh/g under 8000 mA g-1) as well as long-term cycling stability (1130 mAh/g after 900 cycles under 1000 mA g-1). Therefore, this work offers new paths for controllable synthesis and fabrication of high-performance Ge based lithium storage nanomaterials.

A Universal In-Situ Interfacial Growth Strategy for Various MXene-Based van der Waals Heterostructures with Uniform Heterointerfaces: The Efficient Conversion from 3D Composite to 2D Heterostructures.

Two-dimensional (2D) van der Waals heterostructures endow individual 2D material with the novel functional structures, intriguing compositions, and fantastic interfaces, which efficiently provide a feasible route to overcome the intrinsic limitations of single 2D components and embrace the distinct features of different materials. However, the construction of 2D heterostructures with uniform heterointerfaces still poses significant challenges. Herein, a universal in-situ interfacial growth strategy is designed to controllably prepare a series of MXene-based tin selenides/sulfides with 2D van der Waals homogeneous heterostructures. Molten salt etching by-products that are usually recognized as undesirable impurities, are reasonably utilized by us to efficiently transform into different 2D nanostructures via in-situ interfacial growth. The obtained MXene-based 2D heterostructures present sandwiched structures and lamellar interlacing networks with uniform heterointerfaces, which demonstrate the efficient conversion from 3D composite to 2D heterostructures. Such 2D heterostructures significantly enhance charge transfer efficiency, chemical reversibility, and overall structural stability in the electrochemical process. Taking 2D-SnSe2/MXene anode as a representative, it delivers outstanding lithium storage performance with large reversible capacities and ultrahigh capacity retention of over 97% after numerous cycles at 0.2, 1.0, and 10.0 A g-1 current density, which suggests its tremendous application potential in lithium-ion batteries.

Constructing Pd and Cu Crowding Single Atoms by Protein Confinement to Promote Sonogashira Reaction.

For multicenter-catalyzed reactions, it is important to accurately construct heterogeneous catalysts containing multiple active centers with high activity and low cost, which is more challenging compared to homogeneous catalysts because of the low activity and spatial confinement of active centers in the loaded state. Herein, a convenient protein confinement strategy is reported to locate Pd and Cu single atoms in crowding state on carbon coated alumina for promoting Sonogashira reaction, the most powerful method for constructing the acetylenic moiety in molecules. The single-atomic Pd and Cu centers take advantage in not only the maximized atomic utilization for low cost, but also the much-enhanced performance by facilitating the activation of aryl halides and alkynes. Their locally crowded dispersion brings them closer to each other, which facilitates the transmetallation process of acetylide intermediates between them. Thus, the Sonogashira reaction is drove smoothly by the obtained catalyst with a turnover frequency value of 313 h-1, much more efficiently than that by commercial Pd/C and CuI catalyst, conventional Pd and Cu nanocatalysts, and mixed Pd and Cu single-atom catalyst. The obtained catalyst also exhibits the outstanding durability in the recycling test.

Fine Modeling of Multiscale Fracture Cavity Fusion in Fault Solution Reservoirs Based on Multiscale Discrete Crack Modeling Method.

Geological modeling is a three-dimensional (3D) representation of comprehensive geological research results in oil fields. In this paper, first, the comprehensive geological research results were fully applied to establish geological models such as matrix, reservoir, and fractures in the study area. Second, in response to the geological characteristics of carbonate fractured and vuggy reservoirs, various data are integrated. Finally, by collecting and organizing various basic data mentioned above, a refined geological model of the oil reservoir in the study area is established. Results show that (a) Due to the complexity of the distribution of cracks and pores, the presence of these unrelated grids also affects the observation of target cracks and pores. (b) There may be multiple adjacent nodes in the initial access node. The strategy of depth-first traversal is to first access the first adjacent node. (c) There is a significant difference between the connected units extracted solely from static data and the connected units reextracted after fine-tuning the crack position considering dynamic data.

Study on Reservoir Characteristics and 3D Spatial Carving of Fault Solution Reservoirs Based on Geophysical Methods.

At present, research studies on the description of fracture characterization elements in fault solution reservoirs are relatively limited, and further research is needed on contour recognition and characterization methods. In this paper, first, the regional fault system is investigated and the faults are finely identified and characterized. Second, the volume of contour-sensitive attributes of the fault solver is optimized using tensor attributes, amplitude variation, discontinuity detection, and other attributes. Finally, a comprehensive evaluation of the fault solution reservoir is carried out by combining the dynamic production characteristics. Results show that (a) the interior details of fractured reservoirs can be mainly divided into two categories: cave-type reservoirs and fracture-pore-type reservoirs. (b) Fractured and porous reservoirs mainly utilize discontinuous properties and combine well data to calibrate and determine threshold values, ultimately achieving the characterization of interior details of fractured solution bodies. (c) After anisotropic diffusion filtering and fault enhancement, the seismic data was subjected to amplitude gradient disorder detection attribute calculation for multiscale fractures.

The Facile and Controllable Synthesis of Ultrafine Sn Nanocrystals Loaded on Carbon Black for High-Performance Lithium Storage.

Sn and C nanocomposites are ideal anode materials for high-energy and high-power density lithium ion batteries. However, their facile and controllable synthesis for practical applications is still a critical challenge. In this work, a facile one-step method is developed to controllably synthesize ultrafine Sn nanocrystals (< 5 nm) loaded on carbon black (Sn@C) through Na reducing SnCl4 by mechanical milling. Different from traditional up-down mechanical milling method, this method utilizes mechanical milling to trigger bottom-up reduction reaction of SnCl4. The in-situ formed Sn nanocrystals directly grow on carbon black, which results in the homogeneous composite and the size control of Sn nanocrystals. The obtained Sn@C electrode is revealed to possesses large lithium diffusion coefficient, low lithiation energy barrier and stable electrochemical property during cycle, thus showing excellent lithium storage performance with a high reversible capacity (942 mAh g-1 at a current density of 100 mA g-1), distinguished rate ability (480 mAh g-1 at 8000 mA g-1) and superb cycling performance (730 mAh g-1 at 1000 mA g-1 even after 1000 cycles).

Toward Enhancing Low Temperature Performances of Lithium-Ion Transport for Metal-Organic Framework-Based Solid-State Electrolyte: Nanostructure Engineering or Crystal Morphology Controlling.

Metal-organic frameworks (MOFs) have emerged as attractive candidates for Li+ conducting electrolytes due to their regular channels and controllable morphology, making their presence prominent in the field of solid-state lithium batteries. However, most MOF-based electrolytes are researched at or near room temperature, which poses a challenge to their practical applications at low temperatures. Herein, a thin layer flower-shaped 2D Cu-MOF (CuBDC-10)-based solid-state electrolytes (SSEs) for lithium-ion batteries (LIBs) are developed for facilitating Li+ transport at lower temperatures, which achieve an ion conductivity of 10-4 S cm-1 at -30 °C. The CuBDC-10-based SSE exhibits outstanding ionic conductivity over a wide temperature range of -40 to 100 °C (0.073-3.68 × 10-3 S cm-1). This work provides strategies for exploring MOF-based SSEs with high ionic transport performances at low temperatures.

Surface Molecular Engineering for Fully Textured Perovskite/Silicon Tandem Solar Cells.

Developing large-scale monolithic perovskite/silicon tandem devices based on industrial Czochralski silicon wafers will likely have to adopt double-side textured architecture, given their optical benefits and low manufacturing costs. However, the surface engineering strategies that are widely used in solution-processed perovskites to regulate the interface properties are not directly applicable to micrometric textures. Here, we devise a surface passivation strategy by dynamic spray coating (DSC) fluorinated thiophenethylammonium ligands, combining the advantages of providing conformal coverage and suppressing phase conversion on textured surfaces. From the viewpoint of molecular engineering, theoretical calculation and experimental results demonstrate that introducing trifluoromethyl group provide more effective surface passivation through strong interaction and energy alignment by forming a dipole layer. Consequently, the DSC treatment of this bifunctional molecule enables the tandem cells based on industrial silicon wafers to achieve a certified stabilized power conversion efficiency of 30.89 %. In addition, encapsulated devices display excellent operational stability by retaining over 97 % of their initial performance after 600 h continuous illumination.

Novel miR-490-3p/hnRNPA1-b/PKM2 axis mediates the Warburg effect and proliferation of colon cancer cells via the PI3K/AKT pathway.

BACKGROUND: Heterogeneous ribonucleoprotein A1 (hnRNPA1) has been reported to enhance the Warburg effect and promote colon cancer (CC) cell proliferation, but the role and mechanism of the miR-490-3p/hnRNPA1-b/PKM2 axis in CC have not yet been elucidated. AIM: To investigate the role and mechanism of a novel miR-490-3p/hnRNPA1-b/PKM2 axis in enhancing the Warburg effect and promoting CC cell proliferation through the PI3K/AKT pathway. METHODS: Paraffin-embedded pathological sections from 220 CC patients were collected and subjected to immunohistochemical analysis to determine the expression of hnRNPA1-b. The relationship between the expression values and the clinicopathological features of the patients was investigated. Differences in mRNA expression were analyzed using quantitative real-time polymerase chain reaction, while differences in protein expression were analyzed using western blot. Cell proliferation was evaluated using the cell counting kit-8 and 5-ethynyl-2'-deoxyuridine assays, and cell cycle and apoptosis were detected using flow cytometric assays. The targeted binding of miR-490-3p to hnRNPA1-b was validated using a dual luciferase reporter assay. The Warburg effect was evaluated by glucose uptake and lactic acid production assays. RESULTS: The expression of hnRNPA1-b was significantly increased in CC tissues and cells compared to normal controls (P < 0.05). Immunohistochemical results demonstrated significant variations in the expression of the hnRNPA1-b antigen in different stages of CC, including stage I, II-III, and IV. Furthermore, the clinicopathologic characterization revealed a significant correlation between hnRNPA1-b expression and clinical stage as well as T classification. HnRNPA1-b was found to enhance the Warburg effect through the PI3K/AKT pathway, thereby promoting proliferation of HCT116 and SW620 cells. However, the proliferation of HCT116 and SW620 cells was inhibited when miR-490-3p targeted and bound to hnRNPA1-b, effectively blocking the Warburg effect. CONCLUSION: These findings suggest that the novel miR-490-3p/hnRNPA1-b/PKM2 axis could provide a new strategy for the diagnosis and treatment of CC.

Nickel-Cobalt Bimetal Hierarchical Hollow Nanosheets for Efficient Oxygen Evolution in Seawater.

The electrochemical splitting of seawater is promising but also challenging for sustainable hydrogen gas production. Herein, ZIF-67 nanosheets are grown on nickel foam and then etched by Ni2+ in situ to obtain a hierarchical hollow nanosheets structure, which demonstrates outstanding OER performance in alkaline seawater (355 mV at 100 mA cm-2). Diven by a silicon solar panel, an overall electrolysis energy efficiency of 62% is achieved at a high current of 100 mA cm-2 in seawater electrolytes. This work provides a new design route for improving the catalytic activity of metal organic framework materials.

High-Entropy Engineering of Cubic SiP with Metallic Conductivity for Fast and Durable Li-Ion Batteries.

A cost-effective, scalable ball milling process is employed to synthesize the InGeSiP3 compound with a cubic ZnS structure, aiming to address the sluggish reaction kinetics of Si-based anodes for Lithium-ion batteries. Experimental measurements and first-principles calculations confirm that the synthesized InGeSiP3 exhibits significantly higher electronic conductivity, larger Li-ion diffusivity, and greater tolerance to volume change than its parent phases InGe (or Si)P2 or In (or Ge, or Si)P. These improvements stem from its elevated configurational entropy. Multiple characterizations validate that InGeSiP3 undergoes a reversible Li-storage mechanism that involves intercalation, followed by conversion and alloy reactions, resulting in a reversible capacity of 1733 mA h g-1 with an initial Coulombic efficiency of 90%. Moreover, the InGeSiP3-based electrodes exhibit exceptional cycling stability, retaining an 1121 mA h g-1 capacity with a retention rate of ≈87% after 1500 cycles at 2000 mA g-1 and remarkable high-rate capability, achieving 882 mA h g-1 at 10 000 mA g-1. Inspired by the distinctive characteristic of high entropy, the synthesis is extended to high entropy GaCu (or Zn)InGeSiP5, CuZnInGeSiP5, GaCuZnInGeSiP6, InGeSiP2S (or Se), and InGeSiPSSe. This endeavor overcomes the immiscibility of different metals and non-metals, paving the way for the electrochemical energy storage application of high-entropy silicon-phosphides.

Electron Deficient Ir-O Bonds Promote Heterogeneous Ir-Catalyzed Anti-Markovnikov Hydroboration of Alkenes under Mild Neat Conditions.

Tuning electronic characteristics of metal-ligand bonds based on reaction pathways to achieve efficient catalytic processes has been widely studied and proven to be feasible in homogeneous catalysis, but it is scarcely investigated in heterogeneous catalysis. Herein, we demonstrate the regulation of the electronic configuration of Ir-O bonds in an Ir single-atom catalyst according to the borane activation mechanism. Ir-O bonds in Ir1/Ni(OH)x are found to be more electron-poor than those in Ir1/NiOx. Despite the mild solvent-free conditions and ambient temperature, Ir1/Ni(OH)x exhibits outstanding performance for the hydroboration of alkenes, furnishing the desired alkylboronic esters with a turnover frequency value of ≤3060 h-1 and 99% anti-Markovnikov selectivity, which is significantly better than that of Ir1/NiOx (42 h-1). It is further proven that the more electron-poor Ir-O bonds as active centers are more oxidative and so benefit the activation of the H-B bond in the reductive pinacolborane.

Toward Enhancing Performance of Electromagnetic Wave Absorption for Conductive Metal-Organic Frameworks: Nanostructure Engineering or Crystal Morphology Controlling.

Conductive metal-organic frameworks (cMOFs), which have high porosity and intrinsic electron conductivity, are regarded as ideal candidates for electromagnetic wave (EMW) absorption materials. Controlling the nanostructure of absorbers may be one of the effective strategies to improve the electromagnetic wave (EMW) absorption performance. Herein, a series of conductive Cu-HHTP MOFs (HHTP = 2,3,6,7,10,11-hexahydroxytriphenyl hydrates) with different nanostructures or crystal morphologies were successfully synthesized by using different structural inducers to regulate the changes in the morphology, thereby improving the EMW absorption performance. Specifically, when ammonia was used as an inducer, the obtained A-Cu-HHTP with a nanosheet structure exhibited excellent EMW absorption performance. The minimum reflection loss (RLmin) can reach -51.08 dB at 7.25 GHz with a thickness of 4.4 mm, and the maximum effective absorption bandwidth (EAB) can cover 5.73 GHz at 2.5 mm. The influence of the nanostructures of the cMOFs on the dielectric and EMW absorption performance was clarified. The nanosheet structure of A-Cu-HHTP increases its specific surface area, which expands multiple scattering and reflection paths of incident EMW; Meanwhile, the unique structure facilitates the formation of more heterogeneous interfaces, optimizing impedance matching. The significant improvement in EMW performance is mainly attributed to multiple reflections and scattering as well as impedance matching. This work not only provides a simple and effective strategy for improving electromagnetic wave absorption performance but also offers guidelines for preparing morphology functional cMOF materials.

Recent progress and perspectives on metal-organic frameworks as solid-state electrolytes for lithium batteries.

Solid-state electrolytes (SSEs) are the key materials in the new generation of all-solid-state lithium ion/metal batteries. Metal-organic frameworks (MOFs) are ideal materials for developing solid electrolytes because of their structural diversity and porous properties. However, there are several significant issues and obstacles involved, such as lower ion conductivity, a smaller ion transport number, a narrower electrochemical stability window and poor interface contact. In this review, a comprehensive analysis and summary of the unique ion-conducting behavior of MOF-based electrolytes in rechargeable batteries are presented, and the different design principles of MOF-based SSEs are classified and emphasized. Accordingly, four design principles for achieving these MOF-based SSEs are presented and the influence of SSEs combined with MOFs on the electrochemical performance of the batteries is described. Finally, the challenges in the application of MOF materials in lithium ion/metal batteries are explored, and directions for future research on MOF-based electrolytes are proposed. This review will deepen the understanding of MOF-based electrolytes and promote the development of high-performance solid-state lithium ion/metal batteries. This review not only provides theoretical guidance for research on new MOF-based SSE systems, but also contributes to further development of MOFs applied to rechargeable batteries.

Global research on RNA vaccines for COVID-19 from 2019 to 2023: a bibliometric analysis.

Background: Since the global pandemic of COVID-19 has broken out, thousands of pieces of literature on COVID-19 RNA vaccines have been published in various journals. The overall measurement and analysis of RNA vaccines for COVID-19, with the help of sophisticated mathematical tools, could provide deep insights into global research performance and the collaborative architectural structure within the scientific community of COVID-19 mRNA vaccines. In this bibliometric analysis, we aim to determine the extent of the scientific output related to COVID-19 RNA vaccines between 2019 and 2023. Methods: We applied the Bibliometrix R package for comprehensive science mapping analysis of extensive bibliographic metadata retrieved from the Web of Science Core Collection database. On January 11th, 2024, the Web of Science database was searched for COVID-19 RNA vaccine-related publications using predetermined search keywords with specific restrictions. Bradford's law was applied to evaluate the core journals in this field. The data was analyzed with various bibliometric indicators using the Bibliometrix R package. Results: The final analysis included 2962 publications published between 2020 and 2023 while there is no related publication in 2019. The most productive year was 2022. The most relevant leading authors in terms of publications were Ugur Sahin and Pei-Yong, Shi, who had the highest total citations in this field. The core journals were Vaccines, Frontiers in Immunology, and Viruses-Basel. The most frequently used author's keywords were COVID-19, SARS-CoV-2, and vaccine. Recent COVID-19 RNA vaccine-related topics included mental health, COVID-19 vaccines in humans, people, and the pandemic. Harvard University was the top-ranked institution. The leading country in terms of publications, citations, corresponding author country, and international collaboration was the United States. The United States had the most robust collaboration with China. Conclusion: The research hotspots include COVID-19 vaccines and the pandemic in people. We identified international collaboration and research expenditure strongly associated with COVID-19 vaccine research productivity. Researchers' collaboration among developed countries should be extended to low-income countries to expand COVID-19 vaccine-related research and understanding.

Effective Reduction of CO2 with Aromatic Amines into N-Formamides Triggered by Noble-Free Metal-Organic Framework Catalysts Under Mild Conditions.

The reductive transformation of carbon dioxide (CO2) into high-valued N­formamides matches well with the atom economy and the sustainable development intention. Nevertheless, developing a noble-free metal catalyst under mild reaction conditions is desirable and challenging. Herein, a caged metal-organic framework (MOFs) [H2N(CH3)2]2{[Ni3(µ3-O)(XN)(BDC)3]·6DMF}n (1) (XN = 6″-(pyridin-4-yl)-4,2″:4″,4″'-terpyridine), H2BDC = terephthalic acid) is harvested, presenting high thermal and chemical stabilities. Catalytic investigation reveals that 1 as a renewable noble-free MOFs catalyst can catalyze the CO2 reduction conversion with aromatic amines tolerated by broad functional groups at least ten times, resulting in various formamides in excellent yields and selectivity under the mildest reaction system (room temperature and 1 bar CO2). Density functional theory (DFT) theoretical studies disclose the applicable reaction path, in which the CO2 hydrosilylation process is initiated by the [Ni3] cluster interaction with CO2 via η2-C, O coordination mode. This work may open up an avenue to seek high-efficiency noble-free catalysts in CO2 chemical reduction into high value-added chemicals.