Surface Electron Research Articles

First-principles study of adsorption, dissociation, and diffusion of hydrogen on α-U (110) surface

According to the equilibrium crystal shape of α-U, the surface of α-U (110) is more stable and has a larger area fraction than α-U (001). Therefore, the adsorption, dissociation, and diffusion behaviors of H atoms and H2 molecules on the α-U (110) surface were systematically studied by first-principles calculations. The results show that there are only two stable adsorption sites for the H atom: the surface short-bridge site (SB1) and the subsurface short-bridge site (SB2). The adsorption of H2 molecules is divided into chemical adsorption of dissociated H2 molecules and physical adsorption of undissociated H2 molecules, and the LB2-ParL adsorption configuration is the most stable adsorption configuration for H2 molecule adsorption, with an adsorption energy of −0.250 eV. The work function and charge transfer show that adsorption of the H atom or H2 molecule leads to an increase in the work function value of the α-U (110) surface, which enhances the electronic stability of the α-U (110) surface. The projected density of states shows that when the H atom or H2 molecule is close to the α-U (110) surface, the 1s orbital electrons of the H atom will hybridize with the 5f/6d orbital electrons of the nearby surface and subsurface U atoms, and new hybridized orbital peaks appear near the −4.5 eV or −7.3 eV energy level. The climbing image nudged elastic band study shows that the surface free H atoms are very easy to diffuse between the surface short-bridge sites and the subsurface short-bridge sites but the diffusion between the short-bridge site and the triangular center site is extremely difficult.

Insight into the size-dependent activity in Ag/SiO2 catalyzed hydrogenation of dimethyl oxalate to methyl glycolate

Methyl glycolate (MG) is an important building block for synthesizing biodegradable material of polyglycolic acid. Hydrogenation of coal-based dimethyl oxalate (DMO) to MG is quite promising, where Ag-based catalysts exhibited excellent selectivity. Here, a series of Ag/SiO2-x catalysts with particle sizes of 1.4–13.5 nm were prepared, which showed significant structural sensitivity in DMO hydrogenation. For Ag nanoparticles of 1.4–2.7 nm, the turnover frequency (TOF) was linearly increased with the surface electron density of silver, but when the Ag nanoparticles further enlarged, no significant variation of TOF was observed. Combining DFT calculation and experimental results of the model catalyst, triangular nanoplate, it was deduced that the Ag (111) played a dominant role in DMO hydrogenation to MG, originating from the benefited MG desorption as well as promoted dissociation of H2 and DMO. This understanding about Ag particle size effect may provide guidance for designing efficient catalysts for DMO hydrogenation to MG.

Comparative studies of different solutes effects on microstructure and comprehensive performance of coherent precipitation-strengthened Cu–Ni–Al alloys

Multi-componentization can further improve the heating resistance of Cu–Ni–Al alloys, enabling them to withstand more demanding situations. Unfortunately, the limited researches have been done on the wear and corrosion resistance of the heat-resistant Cu–Ni–Al alloys, resulting in the lack of relevant evidence in the practical application. In this work, a comparative study of differential types of trace element, Si (the stronger enthalpy interaction element), Sn (the weaker enthalpy interaction element) Cr or Zr (grain boundary strengthening element), effects on microstructure, wear and corrosion resistance will be done, Furthermore, the effect of different trace elements on the surface electron work function and electrochemical behavior of Cu–Ni–Al alloys is reflected by SPM surface potential model. The results indicate that the precipitation of dual nano-phase and accelerated precipitation of γ′ phase can be realized through the addition of Si, Sn, Cr and Zr, in which the value of δγ-γ′ increase sharply after adding Si and it is not conducive to the preservation of cuboidal γ′ phase. The addition of Si, Cr and Zr can improve electron work function distribution and mechanical property, wear, and corrosion resistance of the alloys, in which Si is more conducive to the improvement of wear resistance and mechanical properties of the alloy, while the alloy with Cr and Zr shows the excellent corrosion resistance. The addition of Sn will weaken the enthalpy interaction of the alloy system, reduce the electron work function of the alloy, and have adverse effects on the wear and corrosion resistance of the alloy.

MOFs-Based Magnetic Nanozyme to Boost Cascade ROS Accumulation for Augmented Tumor Ferroptosis.

The emerging cell death modality of ferroptosis has garnered increasing attention for antitumor treatment but still suffers from low therapeutic efficacy. A metal-organic frameworks (MOFs)-based magnetic nanozyme (PZFH) comprising porphyrin-based Zr-MOF (PCN) on zinc ferrite (ZF) nanoparticles modified with hyaluronic acid, delivering excellent magnetophotonic response for efficient ferroptosis, is reported here. PZFH shows multienzyme-like cascade activity encompassing a photon-triggered oxidase-like catalysis to generate O2 -, which is converted to H2O2 by superoxide dismutase-like activity and subsequent ·OH by magneto-promoted peroxidase (POD) behavior. Newly formed Fe─N coordination and increased Fe2+/Fe3+ levels in the PZFH contribute to the enhanced POD activity, which is further enhanced by accelerated surface electron transfer when exposure to alternated magnetic field. Accumulation of lipid peroxides is eventually accomplished through the conversion of ·OH radicals and singlet oxygen (1O2) produced through laser irradiation. When combined with the depletion of inhibition of glutathione and glutathione peroxidase 4, PZFH exhibits significantly enhanced ferroptosis in tumor-bearing mice, offering insights into nanomedicine for ferroptosis and holding great promise in clinical antitumor therapies.

Potential novel role of the human amniotic membrane as a sustainable hemostat.

Acute hemorrhage can cause significant morbidity and mortality arising from trauma, bleeding disorders, surgical procedures, or obstetric complications. Surgical hemostasis methods may fail to stop acute bleeding due to the complex bleeding dynamics of each bleeding type. Therefore, developing safe and effective topical hemostatic agents remains crucial. The human amniotic membrane (hAM) has established clinical evidence of effectiveness in promoting wound healing and tissue regeneration. Despite its unique biological and immunologic properties and its structural composition of established hemostatic elements, the hemostatic role of hAM has not been yet explored. The present study aimed to investigate this potential role and to describe the development protocol and characterization of hAM-derived topical hemostat. Surface electron microscope (SEM) imaging and Fourier transform infrared (FTIR) spectroscopy were used for characterization, and mouse models with induced peritoneal and tail wound bleeding were employed to evaluate the hemostatic effectiveness using physiological studies, in comparison to a chitosan-based combat-scale hemostat. The hAM hemostat showed a distinctive composition by SEM and FTIR. Applying equal masses of the hAM hemostat, the commercial hemostat, or a combination reduced peritoneal wound bleeding time to averages of 108.4, 86.2, and 76.8 s, respectively, compared to the control group (300 s). Tail wound bleeding times were similarly reduced with no significant difference between the hAM and the commercial hemostat (P values = 0.29, 0.34 in peritoneal and tail wounds, respectively). Neither hemostat affected coagulation time. This study describes a simple cost-effective preparation protocol for a hAM-based hemostatic agent. The long-recognized safety, sustainability, and immunotolerance advantages of hAM can establish superiority over commercial hemostats with reported safety concerns. Robust research validation in larger-scale bleeding models is required for wider applications and severe bleeding types.

Effect of laser treatment on strength of moisture-degraded epoxy adhesive joints and microscopic observation of treated surface

ABSTRACT We examined the effect of laser processing surface treatment on the mechanical strength of adhesion. In addition to laser processing, double cantilever beam (DCB) and lap joint (LJ) specimens were prepared using an epoxy adhesive on aluminum plates that underwent acid etching, sandblasting, and acetone wiping. The open face method was employed to accelerate moisture degradation, and the tensile-shear strength and energy release rate of the specimens were measured. Laser processing resulted in remarkably high values of the measured energy release rate, even when the adhesive deteriorated. To examine the reason for the high strength, we performed a detailed fracture surface analysis and electron microscopic observation of the adhesive interface. When the interface of the fractured surface was observed, the laser treated surface was densely formed with fine filamentous protrusions that held the adhesive well. These filaments exhibited high oxidation resistance and achieved strong adhesion even when the adhesive and adherend deteriorated because of moisture. The laser treated adherend surface exhibited two strong anchoring effects owing to a significant increase in the surface area and the microfilamentous structure on the surface. However, the type of surface treatment did not have a significant effect on the LJ adhesion strength.

Selective CO2 hydrogenation to liquid fuels over Na-decorated FeMgMnOx catalyst with high carbon efficiency

Direct synthesis of liquid fuels (C5+ hydrocarbons) through CO2 hydrogenation has attracted considerable interest. However, it is plagued by high selectivity of C1 by-products (CO and CH4) and low reaction activity. Herein, we report that Na-decorated Fe catalysts promoted by combination of Mg and Mn and investigate their synergistic effect in the catalytic CO2 hydrogenation reaction. The optimized amounts of promoters result in a significant improvement in the catalytic performance of NaFe2O3. The CO2 conversion increases by 1.6-fold, while the total selectivity of CO and CH4 is suppressed to below 21.3 %. The characteristic results reveal the enhanced surface alkalinity and electron transfer favor CO2 adsorption and tuned the local H/C ratio in the vicinity of iron species, thus remarkably promoting the carbon chain growth and limiting the production of C1 products. This study offers a promising approach to modulating the metal electronic environment and improving carbon efficiency for CO2 hydrogenation reactions.

Selectivities of Stepped Cu-M (M = Pt, Ni, Pd, Zn, Ag, Au) Bimetallic Surface Environment for C1 and C2 Pathways.

Copper (Cu) emerges as a highly efficient and cheap catalytic agent for the electrochemical reduction of carbon dioxide (CO2RR), promising a sustainable route toward carbon neutrality. Despite its utility, the Cu catalyst exhibits limitations in terms of product selectivity, highlighting the need for the development of a superior catalyst design. Herein, we present a density functional theory (DFT) investigation into the selectivities of Cu-M (M = Pt, Ni, Pd, Zn, Ag, Au) bimetallic catalysts (BMCs) for the carbon dioxide reduction reaction (CO2RR). The interaction between the metals of Cu-M makes the surface electrons reconstruct so that the d-band center shifts to the Fermi level. In terms of CO2 activation, the Cu-Ni catalyst exhibits superior performance. Additionally, the Cu-Pd catalyst favors the formation of *COH along the reaction pathway, favoring the generation of CH4. Conversely, the Cu-Ni catalyst preferentially produces *CHO, thereby favoring the production of CH3OH. For the Cu-Ag catalyst, the reaction intermediates along the C2 pathway are *CO-*CHO and *COH-*CHO. The Cu-Ni catalyst follows a reaction path that proceeds via *CO-*CO → *CO-*COH → *COH-CHO. On the other hand, the Cu-Pt catalyst exhibits a reaction sequence of *CO-*CO → *CO-*CHO → *OCH-*OCH. This study provides guiding significance for the design of Cu-based bimetallic catalysts aimed at improving the selectivities and efficiency of the CO2RR process.

Adjusting surface electron density of heterostructured NiCo LDH/MXene/NF material to improve its electrocatalytic performance in hydrogen evolution reaction

Hydrogen production by water electrolysis has attracted much interest in the field of renewable energy storage due to its high efficiency and low environmental impact. Catalytic activity of transition metal-based electrode materials can be effectively improved by adjusting their composition and/or structure. In this study, MXene nanosheets are electrophoretically deposited on foamed nickel (MXene/NF), and further coated by NiCo layered double hydroxides (LDH) nanosheets, also by electrophoresis, to obtain the heterostructured and highly conductive NiCo LDH/MXene/NF electrode, highly active in the hydrogen evolution reaction. Uniform surface distribution of three-dimensional interconnected nanosheets is demonstrated by SEM and TEM. The electrode surface is fully wet within 150 ms, indicating excellent hydrophilicity. The highly conductive NiCo LDH/MXene/NF electrode material exhibits a potential overshoot of 123 mV vs. RHE at a current density of 10 mA cm−2, with a Tafel slope of +86.6 mV dec−1. Long-term cyclic testing confirms good stability of the newly prepared electrode material in the hydrogen evolution reaction.

Advanced Prussian Blue Cathodes for Rechargeable Li-Ion Batteries

Taking advantage of fact that the surface electrons of metallic nanoparticles (NPs) can be effectively released even at a low voltage bias, we demonstrate an improvement in the electrochemical performance of nanosized Prussian Blue (PB)-based secondary batteries through the incorporation of bare Ag or Ni NPs in the vicinity of the working PB NPs. It is found that the capacity for electrochemical energy storage of the 17 nm PB-based battery is significantly higher than the capacity of 10 nm PB-based, 35 nm PB-based or 46 nm PB-based batteries. There is a critical PB size for the highest electrochemical energy storage efficiency. The full specific capacity CF of the 17 nm PB-based battery stabilized to 62 mAh/g after 130 charge–discharge cycles at a working current of IW = 0.03 mA. The addition of 14 mass percent of Ag NPs in the vicinity of the PB NPs gave rise to a 32% increase in the stabilized CF. A 42% increase in the stabilized CF could be obtained with the addition of 14 mass percent of Ag NPs on the working electrode of the 35 nm PB-based battery. An enhancement in CF was also found for electrodes incorporating bare Ni NPs but the effect was smaller.

A Study on Boiling Heat Transfer Performance of TiO2-CNTs Hybrid Nanofluid on a Downward-Facing Heating Surface

In-vessel retention through external reactor vessel cooling (IVR-ERVC) is a strategy used to respond to nuclear reactor accidents. One of the key performance indicators determining its feasibility is critical heat flux (CHF). Our focus is on simulating real-world scenarios through surface pool boiling to improve the implementation of the IVR-ERVC strategy with hybrid nanofluids. Two groups of TiO2/COOH-CNTs hybrid nanofluids were prepared: group 1 with different concentrations at the same proportion and group 2 with different proportions at the same total concentration. Researchers compared the improvement of the two groups’ CHF and heat transfer coefficient (HTC), and analyzed the potential mechanism of heat transfer enhancement through roughness of surface, hydrophilicity, and scanning electron microscopy observations. The results showed that a mass concentration of 8 mg:8 mg per liter exhibited the best heat transfer performance, with a CHF enhancement up to 28.21% and an improvement in HTC as well. Meanwhile, correlations between alterations in surface roughness, hydrophilicity, and enhancements in CHF were observed. Finally, by detecting the deposition surface, the possible mechanism of TiO2/COOH-CNTs hybrid nanofluids in enhancing heat transfer was inferred.

Ionization Processes of Negative Corona Discharge Part 1. Review and Experiment

The purpose of the research is an experimental study of physical processes in the near-electrode zones of negative point electrodes in an electronegative gas (air) under the condition of a high-voltage field.Methods. Video image analysis, current-voltage characteristics measurements, and spectroscopy are used. The current-voltage characteristics of the corona discharge ignition voltage in the environment are measured, the problem of experimental identification of surface charges, the mechanism of negative corona discharge ignition, and the ionic structure of streamers is studied, degradation of electrodes during negative corona discharge, spectrum of corona discharge creation and electromagnetic sound.Results. It is shown that at small radii of curvature of needle electrodes, the development of a negative corona discharge is due to the cold emission of electrons, and on flat and slightly curved negative electrodes, due to the capture of surface electrons by electron-withdrawing molecules. The mechanism of ignition of a corona discharge in an electronegative gas with a negative needle, the structure of streamers from negative needles, the emission spectrum and ethonic degradation of electrodes have been studied.Conclusions. The ignition of a negative corona discharge at small radii of the tips of the pointed needles (ro less than tens of microns) is due to the cold emission of electrons followed by impact ionization of neutral molecules. With slightly curved electrodes, the appearance of a negative corona discharge is due to the capture of surface electrons by electronegative gas molecules with subsequent plasma-chemical reactions. The formation of surface electrons depends on many factors: the presence and structure of oxide films (roughness, defects, etc.), which determine the electron work function and form local fields at the tips of microtips. The appearance of a corona discharge leads to degradation of the corona electrodes, expressed in the spraying of the tips of the points and the melting of the needles. In the dark region of the negative corona discharge (U < U*), photons in the in the ultraviolet spectrum (UV spectrum) are emitted, and when U > U*, in addition to UV photons, photons in the visible region of the spectrum are emitted. Glow fluctuations are caused by the chaotic dynamics of the formation of injection centers (melted tubercles - ectons) on the surface of the corona electrode. The ignition of a corona discharge is accompanied by sound emission with a frequency of about 300 Hz.

Surface wettability control and electron transport regulation in zerovalent iron for enhanced removal of emerging polystyrene microplastics-heavy metal contaminants

Emerging microplastics-heavy metal (MPs-HM) contaminants in wastewaters pose an emerging health and environmental risk due to their persistence and increasing ecological risks (e.g., “Trojan horse” effect). Hence, removing MPs in solution and preventing secondary releases of HM has become a key challenge when tackling with MPs pollution. Leveraging the hydrophobic nature of MPs and the electron transfer efficiency from Fe0 to HM, we demonstrate an alkylated and sulfidated nanoscale zerovalent iron (AS-nZVI) featuring a delicate “core-shell-hydrophobic film” nanostructure. Exemplified by polystyrene (PS) MPs-Pb(II) removal, the three nanocomponents offer synergistic functions for the rapid separation of MPs, as well as the reduction and stabilization of Pb(II). The outmost hydrophobic film of AS-nZVI greatly improves the anticorrosion performance of nanoscale zerovalent iron and the enrichment abilities of hydrophobic MPs, achieving a maximum removal capacity of MPs to 2725.87 mgMPs·gFe−1. This MPs enrichment promotes the subsequent reductive removal of Pb(II) through the electron transfer from the iron core of AS-nZVI to Pb(II), a process further strengthened by the introduced sulfur. When considering the inevitable aging of MPs in wastewaters due to mechanical wear or microbial degradation, our study concurrently examines the efficiencies and behaviors of AS-nZVI in removing virgin-MPs-Pb(II) and aged-MPs-Pb(II). The batch results reveal that AS-nZVI has an exceptional ability to remove above 99.6 % Pb(II) for all reaction systems. Overall, this work marks a pioneering effort in highlighting the importance of MPs-toxin combinations in dealing with MPs contamination and in demonstrating the utility of nZVI techniques for MPs-contaminated water purification.

A review on the use of persulfate activation in treating antibiotics-contaminated wastewater

With the progress of science and technology and social development, the misuse of antibiotics has led to water pollution that severely impacts the ecological environment and human health, and the effective treatment of antibiotics-contaminated wastewater has become an urgent problem. Recently, advanced oxidation processes based on persulfate have been widely concerned by scholars because of their good effect in degrading antibiotic pollutants. In this paper, the activation mechanism of persulfate degradation of antibiotic pollutants is firstly reviewed, and the two activation mechanisms of radical pathway and non-radical pathway are distinguished. Then, this paper summarizes the common activation techniques for persulfate treatment of wastewater contaminated with antibiotics, analyzes the principles and characteristics of different activation techniques, and focuses on the non-heterogeneous activation of persulfate in transition metal-based materials and carbon-based materials in terms of the generation of responsive species and the surface electron transfer. Finally, in view of the current needs and difficulties, the author puts forward some suggested research directions and challenges faced, intending to provide some theoretical guidance for the efficient treatment and effective control of antibiotics-contaminated wastewater in the future.

An approach to surface electron density-sensing property correlation in non-stoichiometric boron carbide

The key to most surface phenomena lies in the surface electron density. Particularly, it is the electron density distribution over the surface that primarily controls the overall interaction of the material with the external environment, say in processes like heterogeneous catalysis. Hence, a precise understanding of surface electron density is essential to understand and design improved surface active materials for catalysis and sensing. Surface structure has been determined primarily using surface sensitive techniques like high-energy surface x-ray diffraction (XRD), the crystal truncation rod scattering method, low-energy electron diffraction, scanning transmission electron microscopy, and grazing incidence small angle x-ray scattering. In this work, using aspherical electron density models of crystal structures in different molecular and extended solids, we show a convenient and complementary way of determining high-resolution experimental surface electron density distribution from conventional bulk x-ray diffraction data. The usefulness of our method has been validated by the surface functionality of boron carbide. While certain surfaces in boron carbide show the presence of substantial electron deficient centers, they are absent in others. Based on that, a new surface property of boron carbide has been inferred and has also been validated by chemiresistive gas sensing experiments.

Layered double hydroxides derived prussian blue analogue nanocage confining NiCoP nanoparticles as efficient bifunctional electrocatalyst

Designing novel electrocatalysts with excellent catalytic activity for efficient water splitting is necessary to achieve the large-scale H2/O2 production from renewable resources. In this study, a facile hydrothermal method followed by low-temperature phosphorylation treatment was employed to fabricate a nanocage of prussian blue analogue encapsulating NiCoP nanoparticles (NiCoP@PBA), which was derived from the layered double hydroxide precursor. As a bifunctional non-precious metal electrocatalyst, NiCoP@PBA demonstrates superior performance in KOH electrolyte water splitting, with overpotentials of 59 mV for electrocatalytic hydrogen evolution reaction (HER) and 263 mV for oxygen evolution reaction (OER) at 10 mA cm−2. The catalyst also exhibits low Tafel slopes of 54 mV dec−1 for HER and 120 mV dec−1 for OER, reflecting efficient charge transfer kinetics. DFT simulations show that the Co–N moieties at the heterogeneous interface of NiCoP@PBA can optimize the surface electron distribution and energy states, thus facilitating efficient electron-hole pair separation, significantly enhancing catalytic activity for both HER and OER process, and significantly extending the electrocatalyst's service life. Our approach can be extended to more non-precious metal electrocatalysts, which is significant for the design of efficient bifunctional water splitting electrocatalysts.

Effect of Annealing Temperature on the Structural Properties of Dual Solution Synthesized AlS: ZnS Thin Films

Using two solution-based techniques—solution growth technique (SGT) and sequential ionic layer adsorption and reaction (SILAR) AlS: ZnS alloyed thin films were successfully produced on glass substrates. The sources of Al, Zn, and S were aluminum sulphate (AlSO4.7H20), zinc sulphaate (ZnSO4.7H20), and sodium thiosulphate (Na2S2S03). The complexing agent that was utilized was ethylene diamine tetraacetic acid (EDTA). Using a Master Chef Annealing Machine, the deposited alloyed samples were annealed between 373K and 523K. The scanning electron microscope (SEM) and X-ray diffractometer (XRD) were used for the crystallographic investigations. Samples R1 and R6 AlS: ZnS alloyed thin films exhibit well-defined peaks in their XRD pattern, indicating that they are polycrystalline in nature. We computed their grain sizes. Spectroscopy using Rutherford backscattering (RBS). Analysis using Rutherford backscattering spectroscopy (RBS) verified the composition of aluminum, zinc, and sulfur in the alloyed thin films. The microstructure of the deposited alloyed thin films is revealed by the results of surface electron microscopy. Two significant semiconductor materials that have potential uses in optoelectronics, photovoltaics, and sensing devices are aluminum sulfide (AlS) and zinc sulfide (ZnS). Depositing these materials in thin films at a reasonable cost and with good efficiency is possible with dual solution synthesis. However, the annealing temperature, a crucial factor in establishing the crystal structure, morphology, and optical properties of these films, can have an impact on their structural characteristics. Prior studies have examined how the annealing temperature affects the structural characteristics of AlS and ZnS thin films separately; however, the dual solution-produced AlS: ZnS thin films have not received as much attention. The purpose of this work is to examine how the annealing temperature affects the crystal structure and surface morphology of AlS: ZnS thin films. The results of this investigation can offer significant understanding regarding the refinement of the annealing temperature to produce superior AlS: ZnS thin films for a range of uses. Based on their properties, sulphide alloyed thin films could find applications in microelectronics, window coating, and antireflection coating. They work well as coatings for eyeglasses and as absorber layers for photocells, among other applications.

Efficiency improvement by using metal–insulator-semiconductor structure in InGaN/GaN micro-light-emitting diodes

InGaN/GaN micro-light-emitting diodes (micro-LEDs) with a metal–insulator-semiconductor (MIS) structure on the sidewall are proposed to improve efficiency. In this MIS structure, a sidewall electrode is deposited on the insulating layer-coated sidewall of the device mesa between a cathode on the bottom and an anode on the top. Electroluminescence (EL) measurements of fabricated devices with a mesa diameter of 10 μm show that the application of negative biases on the sidewall electrode can increase the device external quantum efficiency (EQE). In contrast, the application of positive biases can decrease the EQE. The band structure analysis reveals that the EQE is impacted because the application of sidewall electric fields manipulates the local surface electron density along the mesa sidewall and thus controls surface Shockley–Read–Hall (SRH) recombination. Two suggested strategies, reducing insulator layer thickness and exploring alternative materials, can be implemented to further improve the EQE of MIS micro-LEDs in future fabrication.Graphical

A Covalent‐Metal Hybrid‐Link Organic Framework Spray for Portable and Instant Therapy of Deep‐Degree Burn

AbstractDeep burns lead to extensive damage to the dermal layer, necessitating a longer treatment duration than typical skin injuries. Such burn wounds become more susceptible to drug‐resistant bacterial infections, thereby complicating and prolonging the therapeutic process. In this study, a unique spray composed of covalent metal hybrid‐linked organic frameworks (HLOF) material is developed that effectively eradicates methicillin‐resistant Staphylococcus aureus (MRSA) within 20 min by disrupting MRSA's surface electrons, destroying its cell membrane structure, and ultimately causing its demise with an impressive antibacterial rate of 96.7%. This HLOF material exhibited exceptional biological activity and stability. During the wound recovery procedure, HLOF promoted the expression of Vascular endothelial growthfactor(VEGF) to stimulate angiogenesis while inhibiting the proinflammatory factor Tumor necrosis factor alpha (TNF‐α) expression to eliminate inflammation and further enhance wound repair. This study presents an innovative approach for achieving outstanding antibacterial properties and improved biocompatibility through modifications made to common metal organic frameworks (MOFs), thus expanding their potential applications.

Nano-Fe3O4/polymerize aniline/carbon cathode based microbial fuel cell for efficient power generation and uranium separation

Microbial fuel cells (MFCs) have gained increasing attention in the field of uranium-containing wastewater (UCW) treatment as a self-powered bioelectrochemical system (BES) due to its advantages of recovering uranium resources and generating electricity. However, the lack of catalytic active sites on the carbon fiber cathode significantly hinders the reaction performance of surface electrons with uranium ions in solution, thereby limiting the application of MFC. In this study, we propose a carbon brush (CB) cathode modification process that utilizes cyclic voltammetry synthesis technique (CVS) to polymerize aniline (PA) on the surface of carbon fibers and uniformly load nano-Fe3O4 particles (nFe3O4). The loading of PA/nFe3O4 not only significantly improve the catalytic active sites but also enhance the synergistic effect of adsorption and conductivity of CB cathode. Consequently, the nFe3O4/PA/CB-MFC showed excellent ability to continuous power generation and uranium separation. Over eight cycles of uranium separation, the nFe3O4/PA/CB-MFC exhibited an average maximum power density of 15.17 mW/m2 and a uranium separation efficiency of 95.52 %, showcasing substantial enhancements by 2.10-fold and 1.44-fold compared to the CB-MFC, respectively. Our study presents an efficient approach to enhance the efficiency of uranium separation and boost power density of MFC by increase catalytic active sites on carbon-based cathode.