Application of metal-organic frameworks and their derivates for thermal-catalytic C1 molecules conversion.

One-carbon (C1) catalysis refers to the conversion of compounds with a single carbon atom, especially carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4), into clean fuels and valuable chemicals via catalytic strategy is crucial for sustainable and green development. Among various catalytic strategies, thermal-driven process seems to be one of the most promising pathways for C1 catalysis due to the high efficiency and practical application prospect. Notably, the rational design of thermal-driven C1 catalysts plays a vital role in boosting the targeted products synthesis of C1 catalysis, which relies heavily on the choice of ideal active site support, catalyst fabrication precursor, and catalytic reaction field. As a novel crystalline porous material, metal-organic frameworks (MOFs) has made significant progress in the design and synthesis of various functional nanomaterials. However, the application of MOFs in C1 catalysis faces numerous challenges, such as thermal stability, mechanical strength, yield of MOFs, and so on. To overcome these limitations and harness the advantages of MOFs in thermal-driven C1 catalysis, researchers have developed various catalyst/carrier preparation strategies. In this review, we provide a concise overview of the recent advancements in the conversion of CO, CO2, and CH4 into clean fuels and valuable chemicals via thermal-catalytic strategy using MOFs-based catalysts. Furthermore, we discuss the main challenges and opportunities associated with MOFs-based catalysts for thermal-driven C1 catalysis in the future.

Resolution of the reciprocity between radical species from precursor and closed pore formation in hard carbon for sodium storage.

Hard carbon (HC) has emerged as a highly promising anode material for sodium ion batteries, drawing tremendous interest in producing this material with low-cost and easily accessible precursors. The determination of the crucial parameters of precursors influencing the formation of key structures, such as closed pores, in the HC is of paramount importance. Considering the potential role of free radicals in the structural evolution of the precursors, we, for the first time, delve into the impact of radical species on the development of closed pores by electron paramagnetic resonance spectroscopy, with petroleum asphalt as the model system. Our findings reveal that carbon centred radicals, with the g value close to that of the free electron (2.0023), exhibit a propensity to form long-range, well-ordered graphitic structures with lower sodium storage capacity. Conversely, the deliberately incorporated oxygen radicals with the g value over 2.005 require a higher energy for ordering the graphitic structures, leading to the creation of closed pores. As a result, the optimal sample showcases a four-fold increase in plateau capacity for sodium ion storage due to the pore filling process. Our research underscores the pivotal role of employing electron paramagnetic resonance spectroscopy studying the critical structural evolution of functional carbon materials.

Contracting pore channels of a magnesium-based metal-organic framework by decorating methyl groups for effective Xe/Kr separation.

A new magnesium-based metal-organic framework with unprecedented short-chain secondary building units and ultra-micropore channels approaching the kinetic diameters of Xe is fabricated by decorating methyl groups on ligands. Due to the contracted pores, this MOF exhibits very high selectivity values for Xe/Kr, which ranks it among the top porous absorbents.

Electrochemically Exfoliated Graphene Additive-Free Inks for 3D Printing Customizable Monolithic Integrated Micro-Supercapacitors on a Large Scale.

Three-dimensional (3D) printing technology with enhanced fidelity can achieve multiple functionalities and boost electrochemical performance of customizable planar micro-supercapacitors (MSCs), however, precise structural control of additive-free graphene-based macro-assembly electrode for monolithic integrated MSCs (MIMSCs) remains challenging. Here, the large-scale 3D printing fabrication of customizable planar MIMSCs is reported utilizing additive-free, high-quality electrochemically exfoliated graphene inks, which is not required the conventional cryogenic assistance during the printing process and any post-processing reduction. The resulting MSCs reveal an extremely small engineering footprint of 0.025 cm2, exceptionally high areal capacitance of 4900 mF cm-2, volumetric capacitance of 195.6 F cm-3, areal energy density of 2.1 mWh cm-2, and unprecedented volumetric energy density of 23 mWh cm-3 for a single cell, surpassing most previously reported 3D printed MSCs. The 3D printed MIMSC pack is further demonstrated, with the maximum areal cell count density of 16 cell cm-2, the highest output voltage of 192.5 V and the largest output voltage per unit area of 56 V cm-2 up to date are achieved. This work presents an innovative solution for processing high-performance additive-free graphene ink and realizing the large-scale production of 3D printed MIMSCs for planar energy storage.

Advances in the Stability of Catalysts for Electroreduction of CO2 to Formic Acid.

The electroreduction of CO2 to high-value products is a promising approach for achieving carbon neutrality. Among these products, formic acid stands out as having the most potential for industrialization due to its optimal economic value in terms of consumption and output. In recent years, the Faraday efficiency of formic acid from CO2 electroreduction has reached 90~100 %. However, this high selectivity cannot be maintained for extended periods under high currents to meet industrial requirements. This paper reviews excellent work from the perspective of catalyst stability, summarizing and discussing the performance of typical catalysts. Strategies for preparing stable and highly active catalysts are also briefly described. This review may offer a useful data reference and valuable guidance for the future design of long-stability catalysts.

Molecular structure regulation of FCCs enabling N/S co-doped hollow amorphous carbon with enlarged interlayer spacing and rich defects for superior potassium storage.

Constructing high-performance and low-cost carbon anodes for potassium-ion batteries (PIBs) is highly desirable but faces great challenges. In this study, we present a novel approach to fabricating N/S co-doped hollow amorphous carbon (LNSHAC) for superior potassium storage through a template-assisted molecular structure regulation strategy. By tailoring a 3D crosslinked aromatics precursor from fluid catalytic cracking slurry (FCCs), the LNSHAC features a N/S co-doped hollow structure with enlarged interlayer spacing of up to 0.405 nm and rich defects. Such unique microstructure offers fast transport channels for K-ion intercalation/deintercalation and provides more active sites, leading to boosted reaction kinetics and potassium storage capacity. Consequently, the LNSHAC electrode delivers an impressive reversible capacity (466.2 mAh g-1 at 0.1 A/g), excellent rate capability (336.3 mAh g-1 at 2 A/g), and superior cyclic performance (256.9 mAh g-1 after 5000 cycles at 5 A/g with admirable retention of 76.9 %), standing out among the reported carbon-based anodes. When KFeHCF is employed as the cathode, the LNSHAC-based K-ion full cell exhibits a high reversible capacity of 176.6 mAh g-1 at 0.1 A/g and excellent cyclic stability over 200 cycles. This work will inspire the development and application of advanced carbon-based materials for potassium electrochemical energy storage.

Salt Effect Engineering Single Fe-N2P2-Cl Sites on Interlinked Porous Carbon Nanosheets for Superior Oxygen Reduction Reaction and Zn-Air Batteries.

Developing efficient metal-nitrogen-carbon (M-N-C) single-atom catalysts for oxygen reduction reaction (ORR) is significant for the widespread implementation of Zn-air batteries, while the synergic design of the matrix microstructure and coordination environment of metal centers remains challenges. Herein, a novel salt effect-induced strategy is proposed to engineer N and P coordinated atomically dispersed Fe atoms with extra-axial Cl on interlinked porous carbon nanosheets, achieving a superior single-atom Fe catalyst (denoted as Fe-NP-Cl-C) for ORR and Zn-air batteries. The hierarchical porous nanosheet architecture can provide rapid mass/electron transfer channels and facilitate the exposure of active sites. Experiments and density functional theory (DFT) calculations reveal the distinctive Fe-N2P2-Cl active sites afford significantly reduced energy barriers and promoted reaction kinetics for ORR. Consequently, the Fe-NP-Cl-C catalyst exhibits distinguished ORR performance with a half-wave potential (E1/2) of 0.92 V and excellent stability. Remarkably, the assembled Zn-air battery based on Fe-NP-Cl-C delivers an extremely high peak power density of 260 mW cm-2 and a large specific capacity of 812 mA h g-1, outperforming the commercial Pt/C and most reported congeneric catalysts. This study offers a new perspective on structural optimization and coordination engineering of single-atom catalysts for efficient oxygen electrocatalysis and energy conversion devices.

Atomic Zn-Doping Induced Sabatier Optimum in NiZn0.03 Catalyst for CO2 Electroreduction at Industrial-Level Current Densities.

The Sabatier principle defines the essential criteria for an ideal catalyst in heterogeneous catalysis, while reaching the Sabatier optimum is still challenging in catalyst design. Herein, an elegant strategy is described to reach the Sabatier optimum of Ni electrocatalyst in CO2 reduction reaction (CO2 RR) by atomically Zn doping. The incorporation of 3% Zn single atom into Ni lattice leads to the moderate degrade of d-band center via Ni-Zn electronic coupling, which balances the bonding strengths of *COOH and *CO, resulting in a relative low energy barrier for CO2 activation while not being substantially poisoned by CO. Consequently, NiZn0.03 /C exhibits unique catalytic activity (jCO >100 mA cm-2 at -0.6 V), wide potential range for selective CO production (FECO >90% from -0.65 to -1.15 V), and outstanding long-term stability (FECO >90% during 85 h electrolysis at -0.85 V). The results provide valuable insights for the rational fabrication of superior non-noble bimetallic electrocatalysts in CO2 electroreduction.

Insight into Controllable Metal-Support Interactions in Metal/Metal Electrocatalysts for Efficient Energy-Saving Hydrogen Production.

Controllable metal-support interaction (MSI) modulations have long been studied for improving the performance of catalysts supported on metal oxides. However, the corresponding in-depth study for metal1-metal2 (M1-M2) composited configurations is rarely achieved due to the lack of reliable models and manipulation mechanisms of MSI modifications. We modeled ruthenium on copper support (Ru-Cu) metal catalysts with negligible interfacial contact potential (e0.06 V) and investigated MSI-dependent hydrogen evolution reaction (HER) catalysis kinetics induced by an electronic hydroxyl (HO-) modifier. Comprehensive simulations and characterizations confirmed that adjusting the HO- coverage can readily realize the tailorable improvement of MSI, facilitating charge migration at the Ru-Cu interface and optimizing the overall HER pathway on active Ru. As a result, a 5/10 monolayer (ML) HO-modified catalyst (5/10 ML) exhibits superior HER activity and durability owing to the relatively stronger MSI. This catalyst also ensured sustainable and efficient hydrogen generation in a urea electrolyzer with significant energy savings. Our work provides a valuable reference for optimizing the MSI-activity relationship in M1-M2 catalysts that target more than just HER.

Defluoroalkylation of gem-Difluoroalkenes with Alcohols via C-F/C-H Coupling.

A feasible and effective method to synthesize α-fluoroalkenyl alcohols was reported. With the cooperation of photoredox and hydrogen atom transfer (HAT) processes, defluoroalkylations of gem-difluoroalkenes occurred smoothly with alcohols under visible-light irradiation. Notably, the protocols feature broad scopes, mild conditions, and validity for the late-stage functionalization of bioactive molecule derivatives. Mechanistic studies suggested that the reaction occurred through the radical coupling of the alkyl radical and the fluoroalkenyl radical.

Copper-Bridge-Enhanced p-Band Center Modulation of Carbon-Bismuth Heterojunction for CO2 Electroreduction.

Bismuth-based catalysts have advanced CO2 electroreduction to formic acid, but their intrinsic electronic structure remains a key obstacle to achieving a high catalytic performance. Herein, a copper bridge strategy is proposed to enhance electronic modulation effects in bismuth/carbon composites. Density functional theory calculations prove the novel p-d-p hybrid orbitals on the carbon-copper-bismuth heterojunction structure (Bi-Cu/HMCS) could stabilize the HCOO* intermediate and lower the thermodynamic barrier from CO2 to formic acid. With the rapid electron-supplying effect of "copper bridge", the faradaic efficiency of formate reaches 100% (±2%) at a low overpotential of 500 mV and remains above 90% within a wide potential range. Using a solid-state electrolyte device, pure 0.6 M HCOOH is produced at a stable current density of 100 mA cm-2 within 7.5 h, boasting an impressive energy efficiency of 53.8%. This work offers a new strategy for optimizing electronic structure of metal/carbon composite electrocatalysts.

Fabrication of Pillar-Cage Fluorinated Anion Pillared Metal-Organic Frameworks via a Pillar Embedding Strategy and Efficient Separation of SO2 through Multi-Site Trapping.

Flue gas desulfurization is crucial for both human health and ecological environments. However, developing efficient SO2 adsorbents that can break the trade-off between adsorption capacity and selectivity is still challenging. In this work, a new type of fluorinated anion-pillared metal-organic frameworks (APMOFs) with a pillar-cage structure is fabricated through pillar-embedding into a highly porous and robust framework. This type of APMOFs comprises smaller tetrahedral cages and larger icosahedral cages interconnected by embedded [NbOF5 ]2- and [TaOF5 ]2- anions acting as pillars. The APMOFs exhibits high porosity and density of fluorinated anions, ensuring exceptional SO2 adsorption capacity and ultrahigh selectivity for SO2 /CO2 and SO2 /N2 gas mixtures. Furthermore, these two structures demonstrate excellent stability towards water, acid/alkali, and SO2 adsorption. Cycle dynamic breakthrough experiments confirm the excellent separation performance of SO2 /CO2 gas mixtures and their cyclic stability. SO2 -loaded single-crystal X-ray diffraction, Grand canonical Monte Carlo (GCMC) simulations combined with density functional theory (DFT) calculations reveal the preferred adsorption domains for SO2 molecules. The multiple-site host-guest and guest-guest interactions facilitate selective recognition and dense packing of SO2 in this hybrid porous material. This work will be instructive for designing porous materials for flue gas desulfurization and other gas-purification processes.

Carbon-Based Electron Buffer Layer on ZnOx -Fe5 C2 -Fe3 O4 Boosts Ethanol Synthesis from CO2 Hydrogenation.

The conversion of CO2 into ethanol with renewable H2 has attracted tremendous attention due to its integrated functions of carbon elimination and chemical synthesis, but remains challenging. The electronic properties of a catalyst are essential to determine the adsorption strength and configuration of the key intermediates, therefore altering the reaction network for targeted synthesis. Herein, we describe a catalytic system in which a carbon buffer layer is employed to tailor the electronic properties of the ternary ZnOx -Fe5 C2 -Fe3 O4 , in which the electron-transfer pathway (ZnOx →Fe species or carbon layer) ensures the appropriate adsorption strength of -CO* on the catalytic interface, facilitating C-C coupling between -CHx * and -CO* for ethanol synthesis. Benefiting from this unique electron-transfer buffering effect, an extremely high ethanol yield of 366.6 gEtOH kgcat -1 h-1 (with CO of 10 vol % co-feeding) is achieved from CO2 hydrogenation. This work provides a powerful electronic modulation strategy for catalyst design in terms of highly oriented synthesis.

Chronic pulmonary bacterial infection facilitates breast cancer lung metastasis by recruiting tumor-promoting MHCIIhi neutrophils.

Breast cancer can metastasize to various organs, including the lungs. The immune microenvironment of the organs to be metastasized plays a crucial role in the metastasis of breast cancer. Infection with pathogens such as viruses and bacteria can alter the immune status of the lung. However, the effect of chronic inflammation caused by bacteria on the formation of a premetastatic niche within the lung is unclear, and the contribution of specific immune mediators to tumor metastasis also remains largely undetermined. Here, we used a mouse model revealing that chronic pulmonary bacterial infection augmented breast cancer lung metastasis by recruiting a distinct subtype of tumor-infiltrating MHCIIhi neutrophils into the lung, which exhibit cancer-promoting properties. Functionally, MHCIIhi neutrophils enhanced the lung metastasis of breast cancer in a cell-intrinsic manner. Furthermore, we identified CCL2 from lung tissues as an important environmental signal to recruit and maintain MHCIIhi neutrophils. Our findings clearly link bacterial-immune crosstalk to breast cancer lung metastasis and define MHCIIhi neutrophils as the principal mediator between chronic infection and tumor metastasis.

Tailoring the CO2 Hydrogenation Performance of Fe-Based Catalyst via Unique Confinement Effect of the Carbon Shell.

Even though Fe-based catalysts have been widely employed for CO2 hydrogenation into hydrocarbons, oxygenates, liquid fuels, etc., the precise regulation of their physicochemical properties is needed to enhance the catalytic performance. Herein, under the guidance of the traditional concept in heterogeneous catalysis-confinement effect, a core-shell structured catalyst Na-Fe3 O4 @C is constructed to boost the CO2 hydrogenation performance. Benefiting from the carbon-chain growth limitation, tailorable H2 /CO2 ratio on the catalytic interface, and unique electronic property that all endowed by the confinement effect, the selectivity and space-time yield of light olefins (C2 = -C4 = ) are as high as 47.4 % and 15.9 g molFe -1  h-1 , respectively, which are all notably higher than that from the shell-less counterpart. The function mechanism of the confinement effect in Fe-based catalysts are clarified in detail by multiple characterization and density functional theory (DFT). This work may offer a new prospect for the rational design of CO2 hydrogenation catalyst.

Elucidating the Mass Transportation Behavior of Gas Diffusion Layers via a H2 Limiting Current Test.

The gas diffusion layer (GDL), as a key component of proton exchange membrane fuel cells (PEMFCs), plays a crucial role in PEMFC's polarization performance, particularly in mass transport properties at high current densities. To elucidate the correlation between GDLs' structure and their mass transport properties, a limiting current test with the H2 molecular probe was established and employed to investigate three representative GDLs with and without the microporous layer (MPL). By varying humidity and back pressure, the mass transport resistance of three GDLs was measured in an operating fuel cell, and an elaborate analysis of H2 transport was conducted. The results showed that the transport resistance (RDM) of GDLs was affected by the thickness and pore size distribution of the macroporous substrate (MPS) and the MPL. In the process of gas transport, the smaller pore size and thicker MPL increase the force of gas on the pore wall, resulting in an increase in transmission resistance. Through further calculation and analysis, the total transport resistance can be divided into pressure-related resistance (RP) and pressure-independent resistance (RNP). RP mainly originates from the transport resistance in both MPLs and the substrate layers of GDLs, exhibiting a linear relationship to the pressure; RNP mainly originates from the transport resistance in the MPLs. 29BC with thick MPL shows the largest RNP, and T060 without MPL shows the RNP = 0. This methodology enables in situ measurements of mass transport resistances for gas diffusion media, which can be easily applied for developing and deploying PEMFCs.

An integrated multi-omics analysis of identifies distinct molecular characteristics in pulmonary infections of Pseudomonas aeruginosa.

Pseudomonas aeruginosa (P. aeruginosa) can cause severe acute infections, including pneumonia and sepsis, and cause chronic infections, commonly in patients with structural respiratory diseases. However, the molecular and pathophysiological mechanisms of P. aeruginosa respiratory infection are largely unknown. Here, we performed assays for transposase-accessible chromatin using sequencing (ATAC-seq), transcriptomics, and quantitative mass spectrometry-based proteomics and ubiquitin-proteomics in P. aeruginosa-infected lung tissues for multi-omics analysis, while ATAC-seq and transcriptomics were also examined in P. aeruginosa-infected mouse macrophages. To identify the pivotal factors that are involved in host immune defense, we integrated chromatin accessibility and gene expression to investigate molecular changes in P. aeruginosa-infected lung tissues combined with proteomics and ubiquitin-proteomics. Our multi-omics investigation discovered a significant concordance for innate immunological and inflammatory responses following P. aeruginosa infection between hosts and alveolar macrophages. Furthermore, we discovered that multi-omics changes in pioneer factors Stat1 and Stat3 play a crucial role in the immunological regulation of P. aeruginosa infection and that their downstream molecules (e.g., Fas) may be implicated in both immunosuppressive and inflammation-promoting processes. Taken together, these findings indicate that transcription factors and their downstream signaling molecules play a critical role in the mobilization and rebalancing of the host immune response against P. aeruginosa infection and may serve as potential targets for bacterial infections and inflammatory diseases, providing insights and resources for omics analyses.

Nitrogen-doped hierarchical porous carbons derived from biomass for oxygen reduction reaction.

Nowadays biomass has become important sources for the synthesis of different carbon nanomaterials due to their low cost, easy accessibility, large quantity, and rapid regeneration properties. Although researchers have made great effort to convert different biomass into carbons for oxygen reduction reaction (ORR), few of these materials demonstrated good electrocatalytical performance in acidic medium. In this work, fresh daikon was selected as the precursor to synthesize three dimensional (3D) nitrogen doped carbons with hierarchical porous architecture by simple annealing treatment and NH3 activation. The daikon-derived material Daikon-NH3-900 exhibits excellent electrocatalytical performance towards oxygen reduction reaction in both alkaline and acidic medium. Besides, it also shows good durability, CO and methanol tolerance in different electrolytes. Daikon-NH3-900 was further applied as the cathode catalyst for proton exchange membrane (PEM) fuel cell and shows promising performance with a peak power density up to 245 W/g.

Cl2 ⋠- Mediates Direct and Selective Conversion of Inert C(sp3 )-H Bonds into Aldehydes/Ketones.

Developing new reactive pathway to activate inert C(sp3 )-H bonds for valuable oxygenated products remains a challenge. We prepared a series of triazine conjugated organic polymers to photoactivate C-H into aldehyde/ketone via O2 →H2 O2 →⋅OH→Cl⋅→Cl2 ⋅- . Experiment results showed Cl2 ⋅- could successively activate C(sp3 )-H more effectively than Cl⋅ to generate unstable dichlorinated intermediates, increasing the kinetic rate ratio of dichlorination to monochlorination by a factor of 2,000 and thus breaking traditional dichlorination kinetic constraints. These active intermediates were hydrolyzed into aldehydes or ketones easily, when compared with typical stable dichlorinated complexes, avoiding chlorinated by-product generation. Moreover, an integrated two-phase system in an acid solution strengthened the Cl2 ⋅- mediated process and inhibited product overoxidation, where the conversion rate of toluene reached 16.94 mmol/g/h and the selectivity of benzaldehyde was 99.5 %. This work presents a facile and efficient approach for selective conversion of inert C(sp3 )-H bonds using Cl2 ⋅- .

Combination of Mn-Mo Oxide Nanoparticles on Carbon Nanotubes through Nitrogen Doping to Catalyze Oxygen Reduction.

An efficient and low-cost oxygen catalyst for the oxygen reduction reaction (ORR) was developed by in situ growth of Mn-Mo oxide nanoparticles on nitrogen-doped carbon nanotubes (NCNTs). Doped nitrogen effectively increases the electron conductivity of the MnMoO4@NCNT complex and the binding energy between the Mn-Mo oxide nanoparticles and carbon nanotubes (CNTs), leading to fast charge transfer and more catalytically active sites. Combining Mn and Mo with NCNTs improves the catalytic activity and promotes both electron and mass transfers, greatly enhancing the catalytic ability for ORR. As a result, MnMoO4@NCNT exhibited a comparable half-wave potential to commercial Pt/C and superior durability, demonstrating great potential for application in renewable energy conversion systems.