Efficient sulfur atom-doped three-dimensional porous MXene-assisted sodium ion batteries.

Recently, it has been reported that MXene is a promising pseudocapacitive material for energy storage, primarily due to its intercalation mechanism. However, Ti3C2Tx MXenes face challenges, such as inadequate layer spacing and low specific capacity, which greatly hinder their potential as anode materials for sodium storage. In this study, MXene was doped with sulfur to create a three-dimensional porous structure that resulted in an increased layer spacing. The sulfur-doped porous MXene (SPM) demonstrated exceptional performance as sodium ion battery anodes, with a capacity of 335.2 mA h g-1 after 490 cycles at 2 A g-1 and a long-term cycling performance of 256.1 mA h g-1 even after 2480 cycles at 5 A g-1. It is worth noting that the porous structure formed after sulfur-doping exhibits superior sodium storage performance compared to previously reported MXene-based electrodes. This highlights the feasibility of the structural construction strategy, offering an effective solution for energy storage and conversion applications.

Smart Dual-Exsolved Self-Assembled Anode Enables Efficient and Robust Methane-Fueled Solid Oxide Fuel Cells.

Perovskite oxides have emerged as alternative anode materials for hydrocarbon-fueled solid oxide fuel cells (SOFCs). Nevertheless, the sluggish kinetics for hydrocarbon conversion hinder their commercial applications. Herein, a novel dual-exsolved self-assembled anode for CH4 -fueled SOFCs is developed. The designed Ru@Ru-Sr2 Fe1.5 Mo0.5 O6-δ (SFM)/Ru-Gd0.1 Ce0.9 O2-δ (GDC) anode exhibits a unique hierarchical structure of nano-heterointerfaces exsolved on submicron skeletons. As a result, the Ru@Ru-SFM/Ru-GDC anode-based single cell achieves high peak power densities of 1.03 and 0.63 W cm-2 at 800 °C under humidified H2 and CH4 , surpassing most reported perovskite-based anodes. Moreover, this anode demonstrates negligible degradation over 200 h in humidified CH4 , indicating high resistance to carbon deposition. Density functional theory calculations reveal that the created metal-oxide heterointerfaces of Ru@Ru-SFM and Ru@Ru-GDC have higher intrinsic activities for CH4 conversion compared to pristine SFM. These findings highlight a viable design of the dual-exsolved self-assembled anode for efficient and robust hydrocarbon-fueled SOFCs.

Rosa Roxburghii Tratt Fruit Extract Prevents Dss-Induced Ulcerative Colitis in Mice by Modulating the Gut Microbiota and the IL-17 Signaling Pathway.

Ulcerative colitis (UC) is a non-specific inflammatory bowel illness characterized by intestinal mucosal barrier degradation, inflammation, oxidative damage, and gut microbiota imbalances. Rosa roxburghii Tratt Fruit extract (RRTE) was extracted from Rosa roxburghii Tratt fruit, exhibiting an excellent prevention effect against UC; RRTE could prevent the damage of DSS-induced human normal colonic epithelial (NCM 460) cells, especially in cell viability and morphology, and oxidative damage. Additionally, in UC mice, RRTE could limit the intestinal mucosal barrier by increasing the expression of intestinal tight junction proteins and mucin, reducing inflammation and oxidative damage in colon tissue. More importantly, RRTE can increase the abundance of beneficial bacteria to regulate gut microbiota such as Ruminococcus, Turicibacter, and Parabacteroides, and reduce the abundance of harmful bacteria such as Staphylococcus and Shigella. Furthermore, transcriptomics of colonic mucosal findings point out that the beneficial effect of RRTE on UC could be attributed to the modulation of inflammatory responses such as the IL-17 and TNF signaling pathways. The qPCR results confirm that RRTE did involve the regulation of several genes in the IL-17 signaling pathway. In conclusion, RRTE could prevent DSS-induced damage both in vitro and in vivo.

A-Site Nonstoichiometric BaxCo0.4Fe0.4Zr0.1Y0.1O3-δ Cathode for Protonic Ceramics Fuel Cells.

Highly active triple (proton, oxygen-ion, and electron) conducting materials BaxCo0.4Fe0.4Zr0.1Y0.1O3-δ (BxCFZY, x = 0.9-1.1) were prepared and characterized as potential cathodes for protonic ceramic fuel cells (PCFCs) in this work. The crystal structure, oxygen vacancy concentration, electrical conductivity, oxygen ion transfer properties, and electrochemical performance of BxCFZY oxides were systematically evaluated. The electrical conductivity of BxCFZY decreases but oxygen vacancies increase with increasing Ba content, indicating that the charge compensation was mainly achieved by the production of oxygen vacancy rather than the increase in the valence of transition metal cations. The power density of 1170 mW cm-2 and the polarization resistance of 0.05 Ω cm2 were achieved at 700 °C for the anode-supported single cells with B1.1CFZY cathode, suggesting that the excess A site on the BxCFZY had a positive effect on the catalytic activity for the oxygen reduction reaction. Furthermore, the distribution of relaxation time (DRT) analysis method was adopted to determine the electrochemical processes of the cells with BxCFZY cathodes. The calculated results confirmed that the cell with B1.1CFZY cathode exhibited the optimum performance due to the best oxygen ion transfer properties in BxCFZY cathodes.

Boosting the Electrocatalytic Activity of Pr0.5Ba0.5FeO3-δ via Ni Doping in Symmetric Solid Oxide Electrolysis Cells.

Symmetric solid oxide electrolysis cells (SSOECs) have garnered significant scientific interest due to their simplified cell architecture, robust operational reliability, and cost-effectiveness, for which a highly electrocatalytically active electrode is the decisive main factor. This work evaluates the electrochemical performance of Ni-doped Pr0.5Ba0.5FeO3-δ (PBF) perovskite materials, with a focus on Pr0.5Ba0.5Fe0.8Ni0.2O3-δ (PBFN). The experimental findings herein prove the exceptional electrocatalytic ability of PBFN in facilitating the oxygen evolution and carbon dioxide reduction reaction, surpassing the electrochemical performance of PBF. In addition, the PBFN symmetric cell has excellent performance for CO2 electrolysis, and the cell has a low polarization resistance value of 0.1 Ω·cm2. Moreover, it achieves an impressive current density value of 1.118 A·cm-2 under operating conditions of 2.0 V and 800 °C, which is superior to those of the PBF symmetric cell and the PBFN asymmetric cell. It also has a good structural and performance stability. These results imply a bright development prospect of PBFN as electrodes for SSOECs.

Atomistic Insights into Medium-Entropy Perovskites for Efficient and Robust CO2 Electrolysis.

Solid oxide electrolysis cells (SOECs) show great promise in converting CO2 to valuable products. However, their practicality for the CO2 reduction reaction (CO2RR) is restricted by sluggish kinetics and limited durability. Herein, we propose a novel medium-entropy perovskite, Sr2(Fe1.0Ti0.25Cr0.25Mn0.25Mo0.25)O6-δ (SFTCMM), as a potential electrode material for symmetrical SOEC toward CO2RR. Experimental and theoretical results unveil that the configuration entropy of SFTCMM perovskites contributes to the strengthened metal 3d-O 2p hybridization and the reduced O 2p bond center. This variation of electronic structure benefits oxygen vacancy creation and diffusion as well as CO2 adsorption and activation and ultimately accelerates CO2RR and oxygen electrocatalysis kinetics. Notably, the SFTCMM-based symmetrical SOEC delivers an excellent current density of 1.50 A cm-2 at 800 °C and 1.5 V, surpassing the prototype Sr2Fe1.5Mo0.5O6-δ (SFM, 1.04 A cm-2) and most of the state-of-the-art electrodes for symmetrical SOECs. Moreover, the SFTCMM-based symmetrical SOEC demonstrates stable CO2RR operation for 160 h.

Effects of Rosa roxburghii Tratt on Ulcerative Colitis: An Integrated Analysis of Network Pharmacology and Experimental Validation.

Rosa roxburghii Tratt is a traditional Chinese plant that has been used to treat different inflammatory diseases. The purpose of this study was to investigate the mechanism of action of Rosa roxburghii Tratt extract (RRTE) against ulcerative colitis (UC) using network pharmacology and experimental validation. HPLC-Q/Orbitrap MS was used to rapidly identify the substances contained in RRTE after extracting the active components from the fruit. Then, network pharmacology combined with molecular docking was used to explore the critical target and potential mechanism of RRTE against UC using the active ingredients in RRTE as the research object. Data are presented in a visual manner. Finally, the pharmacological effects of RRTE in alleviating UC were further verified using a DSS-induced UC model of NCM460. The results showed that 25 components in RRTE were identified. A total of 250 targets of the active components and 5376 targets associated with UC were collected. Furthermore, a systematic analysis of the Protein-Protein Interaction (PPI) networks suggests that epidermal growth factor receptor (EGFR), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), and serine/threonine kinase 1 (AKT1) are critical targets for RRTE in the treatment of UC. A comprehensive regulatory network analysis showed that RRTE alleviated UC through the EGFR-mediated PI3K/Akt pathway, and molecular docking showed that active components could strongly bind to EGFR, PIK3R1, and AKT1. In addition, RRTE alleviated dextran sulfate sodium salt (DSS)-induced cell injury and significantly decreased the protein expression levels of EGFR, PIK3R1, and p-AKT in NCM460 cells in vitro. Furthermore, RRTE significantly regulated the expression of the apoptosis-related proteins Apoptotic protease-activating factor 1 (Apaf1), cleaved caspase-3, B-cell lymphoma-2 (Bcl2), and Bcl2 associated X protein (Bax). In conclusion, the components of RRTE are complex, and RRTE can relieve UC through the EGFR-mediated PI3K/Akt pathway.

Fabrication of super-hydrophilic and highly open-porous poly (lactic acid) scaffolds using supercritical carbon dioxide foaming.

Porous poly (lactic acid) (PLA)-based scaffolds have been widely used as a promising product in tissue engineering. However, it is still a challenge to prepare the PLA-based scaffolds with high expansion ratio, good hydrophilicity, and excellent cytocompatibility by a green and cost-effective fabrication approach. Herein, we prepared porous PLA-based scaffolds using carbon dioxide (CO2) as the physical foaming agent. To improve the hydrophilicity and foaming behavior of PLA, poly (ethylene glycol) (PEG) was selected as a good additive to blend with PLA. It revealed that the introduction of PEG could improve the foaming behavior of PLA and promote the formation of opening cells via reducing the matrix strength of PLA. The obtained 3D PLA/PEG scaffolds exhibited high expansion ratio (9.1), high open-cell content (95.2%), and super-hydrophilicity (water contact angle 0°). Additionally, the mouse fibroblast NIH/3T3 cells with live/dead cell fluorescence staining assay was utilized to examine the biocompatibility of PLA/PEG scaffolds. The result demonstrated that the proliferation ratio of NIH/3 T3 cells on the surface of PLA/PEG scaffolds was higher than that of PLA scaffolds, indicating that the highly interconnected cell structure was conducive to cell adhesion and attachment. Consequently, such hydrophilic open-cell structure obtained by adding PEG into PLA possesses great potential for use in tissue engineering.

Enhancing the Intrinsic Activity and Stability of Perovskite Cobaltite at Elevated Temperature Through Surface Stress.

Perovskite-based oxides attract great attention as catalysts for energy and environmental devices. Nanostructure engineering is demonstrated as an effective approach for improving the catalytic activity of the materials. The mechanism for the enhancement, nevertheless, is still not fully understood. In this study, it is demonstrated that compressive strain can be introduced into freestanding perovskite cobaltite La0.8 Sr0.2 CoO3- δ (LSC) nanofibers with sufficient small size. Crystal structure analysis suggests that the LSC fiber is characterized by compressive strain along the ab plane and less distorted CoO6 octahedron compared to the bulk powder sample. Accompanied by such structural changes, the nanofiber shows significantly higher oxygen reduction reaction (ORR) activity and better stability at elevated temperature, which is attributed to the higher oxygen vacancy concentration and suppressed Sr segregation in the LSC nanofibers. First-principle calculations further suggest that the compressive strain in LSC nanofibers effectively shortens the distance between the Co 3d and O 2p band center and lowers the oxygen vacancy formation energy. The results clarify the critical role of surface stress in determining the intrinsic activity of perovskite oxide nanomaterials. The results of this work can help guide the design of highly active and durable perovskite catalysts via nanostructure engineering.

Facile Preparation of Mesoporous MCM-48 Containing Silver Nanoparticles with Fly Ash as Raw Materials for CO Catalytic Oxidation.

An environmentally friendly method was proposed to prepare mesoporous Mobil Composition of Matter No.48 (MCM-48) using fly ash as the silica source. Silver nanoparticles were infiltrated on MCM-48 facilely by an in situ post-reduction method and evaluated as an effective catalyst for CO oxidation. The as-prepared MCM-48 and Ag/MCM-48 nanoparticles were characterized by XRD, N2 adsorption/desorption, and TEM. Investigations by means of XPS for Ag/MCM-48 were performed in order to illuminate the surface composition of the samples. Studies revealed the strong influence of the loading of Ag nanoparticles on catalysts in the oxidation of CO. CO conversion values for Ag/MCM-48 of 10% and 100% were achieved at temperatures of 220 °C and 270 °C, respectively, indicating that the Ag-decorated MCM-48 catalyst is extremely active for CO oxidation.

Charge-Transfer Modeling and Polarization DRT Analysis of Proton Ceramics Fuel Cells Based on Mixed Conductive Electrolyte with the Modified Anode-Electrolyte Interface.

A charge-transfer model considering the mixed conductivities of proton, oxygen ion, and free electron in interface-modified La2Ce2O7 (LCO) electrolyte is designed to analyze the characteristics of proton ceramics fuel cell in the field of the open-circuit voltage, internal short-circuit current, proton-transfer number, discharging curves, oxygen/hydrogen partial pressure, and cell efficiencies. The properties of anode-supported single cells with the modified anode-electrolyte interface containing an in situ formed doped BaCeO3 reaction layer are compared to those of unmodified cells at various temperatures T and H2O partial pressures. Besides, the electrochemical impedance spectroscopies of both cells were investigated by the relaxation time distribution to distinguish different polarization processes. The results indicated that the reaction interface layer can effectively reduce the internal short-circuit current density and increase the proton-transfer number of electrolytes. Importantly, the NiO-BaZr0.1Ce0.7Y0.2O3-δ anode can also make more protons transfer from anode to cathode and participate in the cathodic reaction for LCO-based proton ceramics fuel cell. The polarization of the cell decreases with the increase of water partial pressure, which leads to the increase of open-circuit voltage and cell efficiency.

The determining factor for interstitial oxygen formation in Ruddlesden-Popper type La2NiO4-based oxides.

The interstitial oxygen formation mechanism in La2NiO4-based oxides was studied using soft X-ray absorption spectroscopy. When the interstitial oxygen concentration increased, the pre-edge peak of O K-edge spectra increased while Ni L-edge spectra was almost invariant. These spectral changes strongly suggest the significant contribution of ligand oxygen to interstitial oxygen formation by providing/accepting electronic charge carriers. The variation of the integrated peak intensity of the O K-edge strongly suggests that interstitial oxygen formation is determined by the equilibrium unoccupied pDOS of ligand oxygen. From this hypothesis, we propose that modulating the electronic structure is the key to control the capability of interstitial oxygen formation in La2NiO4-based oxides.

Oxygen nonstoichiometry, the defect equilibrium model and thermodynamic quantities of the Ruddlesden-Popper oxide Sr3Fe2O(7-δ).

Oxygen nonstoichiometry of the Ruddlesden-Popper oxide Sr3Fe2O7-δ was measured at intermediate temperatures (773-1073 K) by coulometric titration and high temperature gravimetry. The oxygen nonstoichiometric behavior was analyzed using the defect equilibrium model with localized electrons. From the defect chemical analysis, estimated oxygen vacancy concentration at the O3 sites increases and at the O1 sites decreases with the increasing temperature. This characteristic behavior is considered to be caused by the redistribution of oxygen and vacancies between the O1 and O3 sites. The obtained thermodynamic quantities of the partial molar enthalpy of oxygen, h(O) - h°(O), and the partial molar entropy of oxygen, s(O) - s°(O), calculated from the Gibbs-Helmholtz equation are in good agreement with those from the statistical thermodynamic calculation based on the defect equilibrium model, indicating that the proposed defect equilibrium model is reasonable.