A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals

The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance.

Exploring the Core-shell Structure of BaTiO3-based Dielectric Ceramics Using Machine Learning Models and Interpretability Analysis

A machine learning(ML)-based random forest(RF)classification model algorithm was employed to investigate the main factors affecting the formation of the core-shell structure of BaTiO_(3)-based ceramics and their interpretability was analyzed by using Shapley additive explanations(SHAP).An F1-score changed from 0.8795 to 0.9310,accuracy from 0.8450 to 0.9070,precision from 0.8714 to 0.9000,recall from 0.8929 to 0.9643,and ROC/AUC value of 0.97±0.03 was achieved by the RF classification with the optimal set of features containing only 5 features,demonstrating the high accuracy of our model and its high robustness.During the interpretability analysis of the model,it was found that the electronegativity,melting point,and sintering temperature of the dopant contribute highly to the formation of the core-shell structure,and based on these characteristics,specific ranges were delineated and twelve elements were finally obtained that met all the requirements,namely Si,Sc,Mn,Fe,Co,Ni,Pd,Er,Tm,Lu,Pa,and Cm.In the process of exploring the structure of the core-shell,the doping elements can be effectively localized to be selected by choosing the range of features.

Regulating zinc ion transport behavior and solvated structure towards stable aqueous Zn metal batteries

Aqueous Zn metal batteries(AZMBs)with intrinsic safety,high energy density and low cost have been regarded as promising electrochemical energy storage devices.However,the parasitic reaction on metallic Zn anode and the incompatibility between electrode and electrolytes lead to the deterioration of electrochemical performance of AZMBs during the cycling.The critical point to achieve the stable cycling of AZMBs is to properly regulate the zinc ion solvated structure and transfer behavior between metallic Zn anode and electrolyte.In recent years,numerous achievements have been made to resolve the formation of Zn dendrite and interface incompatible issues faced by AZMBs via optimizing the sheath structure and transport capability of zinc ions at electrode-electrolyte interface.In this review,the challenges for metallic Zn anode and electrode-electrolyte interface in AZMBs including dendrite formation and interface characteristics are presented.Following the influences of different strategies involving designing advanced electrode structu re,artificial solid electrolyte interphase(SEI)on Zn anode and electrolyte engineering to regulate zinc ion solvated sheath structure and transport behavior are summarized and discussed.Finally,the perspectives for the future development of design strategies for dendrite-free Zn metal anode and long lifespan AZMBs are also given.

Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction

The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.

From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption

The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.

Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures

Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented.

Application of Monodisperse Thermo-Responsive Composite Microgels with Core-Shell Structure Based on Au@Ag Bimetallic Nanorod as Core in Surface Enhanced Raman Spectroscopy Substrate

The monodisperse Au@Ag bimetallic nanorod is encapsulated by crosslinked poly( N-isopropylacrylamide)( PNIPAM) to produce thermo-responsive composite microgel with well-defined core-shell structure( Au@ Ag NR@ PNIPAM microgel)by seed-precipitation polymerization method using butenoic acid modified Au @ Ag NRs as seeds. When the temperature of the aqueous medium increases from 20℃ to 50℃,the localized surface plasmon resonance( LSPR) band of the entrapped Au @ Ag NR is pronouncedly red-shifted because of the decreased spatial distances between them as a result of shrinkage of the microgels,leading to their plasmonic coupling. The temperature tunable plasmonic coupling is demonstrated by temperature dependence of the surface enhanced Raman spectroscopy( SERS) signal of 1-naphthol in aqueous solution. Different from static plasmonic coupling modes from nanostructured assembly or array system of noble metals,the proposed plasmonic coupling can be dynamically controlled by environmental temperature. Therefore, the thermo responsive hybrid microgels have potential applications in mobile LSPR or SERS microsensors for living tissues or cells.

Recent advances in core-shell organic framework-based photocatalysts for energy conversion and environmental remediation

Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and functionality.The existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were introduced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.

Mitigating Lattice Distortion of High‑Voltage LiCoO_(2)via Core‑Shell Structure Induced by Cationic Heterogeneous Co‑Doping for Lithium‑Ion Batteries

Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries.

Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance

The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the problem.Two types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)layer.The morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was validated.The grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)binder.Due to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,respectively.Furthermore,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted polymers.These findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns.

Suppression of Co(Ⅱ)ion deposition and hazards:Regulation of SEI film composition and structure

Despite the presence of Li F components in the solid electrolyte interphase(SEI)formed on the graphite anode surface by conventional electrolyte,these Li F components primarily exist in an amorphous state,rendering them incapable of effectively inhibiting the exchange reaction between lithium ions and transition metal ions in the electrolyte.Consequently,nearly all lithium ions within the SEI film are replaced by transition metal ions,resulting in an increase in interphacial impedance and a decrease in stability.Herein,we demonstrate that the SEI film,constructed by fluoroethylene carbonate(FEC)additive rich in crystalline Li F,effectively inhibits the undesired Li^(+)/Co^(2+)ion exchange reaction,thereby suppressing the deposition of cobalt compounds and metallic cobalt.Furthermore,the deposited cobalt compounds exhibit enhanced structural stability and reduced catalytic activity with minimal impact on the interphacial stability of the graphite anode.Our findings reveal the crucial influence of SEI film composition and structure on the deposition and hazards associated with transition metal ions,providing valuable guidance for designing next-generation electrolytes.

Fabrication of Core-Shell Hydrogel Bead Based on Sodium Alginate and Chitosan for Methylene Blue Adsorption

A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calcium ions(Ca^(2+)).The shell,composed of a chitosan/activated carbon mixture,was then coated onto the core.Fourier transform infrared spectroscopy confirmed the grafting polymerization of acrylamide onto sodium alginate.Scanning electron microscopy images showed the core-shell structure.The core exhibited a high water uptake ratio,facilitating the diffusion of methylene blue into the core.During the diffusion process,the methylene blue was first adsorbed by the shell and then further adsorbed by the core.Adsorption tests showed that the coreshell structure had a larger adsorption capacity than the core alone.The shell effectively enhanced the adsorption capacity to methylene blue compared to the single core.Methylene blue was adsorbed by activated carbon and chitosan in the shell,and the residual methylene blue diffused into the core and was further adsorbed.

Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction

Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions.

Generation of structured light beams with polarization variation along arbitrary spatial trajectories using tri-layer metasurfaces

Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajectory.In particular,along the optical axis,the polarization state is either constant or varies continuously in each output plane.Here,we develop innovative spatially structured light beams with continually changing polarization along any arbitrary spatial transmission trajectories.With tri-layer metallic metasurfaces,the geometric characteristics of each layer structure can be adjusted to modulate the phase and polarization state of the incident terahertz(THz)wave.The beam will converge to the predefined trajectory along several paths to generate a Bessel-like beam with longitudinal polarization changes.We demonstrate the versatility of the approach by designing two THz-band structured light beams with varying polarization states along the spatial helical transmission trajectory.Continuous linear polarization changes and linear polarization to right circular polarization(RCP)and back to linear polarization changes are realized respectively.The experimental results are basically consistent with the simulated results.Our proposal for arbitrary trajectory structured light beams with longitudinally varying polarization offers a practical method for continuously regulating the characteristics of spatial structured light beams with non-axial transmission.This technique has potential uses in optical encryption,particle manipulation,and biomedical imaging.

Immobilization of Oxyanions on the Reconstructed Heterostructure Evolved from a Bimetallic Oxysulfide for the Promotion of Oxygen Evolution Reaction

Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La_(2)O_(2)S prototype is fabricated as a binder-free precatalyst for alkaline OER.The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La,Ni,O,and S species during OER,which assures the adsorption and stabilization of the oxyanion SO_(4)^(2-)onto the surface of the deeply reconstructed porous heterostructure composed of confining Ni OOH nanodomains by La(OH)_3 barrier.Such coupling,confinement,porosity and immobilization enable notable improvement in active site accessibility,phase stability,mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates.The optimized electrocatalyst delivers exceptional alkaline OER activity and durability,outperforming most of the Ni-based benchmark OER electrocatalysts.

Pressure-induced phase transition and electronic structure evolution in layered semimetal HfTe_(2)

Motivated by the recent experimental work,the pressure-induced structural transition of well-known two-dimensional(2D)1T-Hf Te_(2)was investigated up to 50 GPa through the advanced CALYPSO structure search technique combined with the first-principles calculations.Our calculations suggested that the 1T-Hf Te_(2)will first transform to C2/m phase at 3.6 GPa with a volume reduction of 7.6%and then to P62m phase at 9.6 GPa with a volume collapse of 4.6%.The occurrences of 3D C2/m and P62m phases mainly originated from the enhanced Te-Te interlayer coupling and the drastic distortions of Hf-Te polyhedrons in P3m1 phase under compression.Concomitantly,the coordination number of Hf atoms increased from six in P3m1 to eight in C2/m and eventually to nine in P62m at elevated pressure.The metallic and semimetallic nature of C2/m and P62m phases were characterized,and the evidence of the reinforced covalent interactions of Te-Hf and Te-Te orbitals in these two novel high-pressure phases were manifested by the atom-projected electronic DOS and Bader charge.

Electrode structure enabling dendrite inhibition for high cycle stability quasi-solid-state lithium metal batteries

Lithium(Li)metal batteries(LMBs)are widely regarded as the ultimate choice for the next generation of high-energy–density batteries.However,the uncontrollable growth of Li dendrites formed by inhomogeneous deposition seriously hinders its commercialization.Although many studies have achieved significant results in inhibiting the formation of Li dendrites,it is still impossible to eradicate them completely.Therefore,regulating the deposition behavior,such as the growth direction of unevenly deposited Li,is preferable to unilaterally suppressing them in some cases.Here we report a structured anode that can confine the deposited Li within holes and tune it to become vertical-up/horizontal-centripetal mixed growth mode by optimizing the electric field/Li^(+)concentration gradient.The Li^(+) adsorbed by the poly(amic acid)(PAA)insulating layer coated on the anode surface can form the Li^(+)concentration gradient pointing to the center of the hole.Combined with the special electric field formed by the hole structure,it is favorable for the Li^(+)to move into the vertically arrayed holes and simultaneously deposit on the bottom and walls.Furthermore,both in-situ and ex-situ observations confirm that the growth mode is changed and the Li deposition morphology is denser,which can greatly delay capacity fading and prolong cycle life in both liquid and quasi-solid-state LMBs.All the results show that the novel anode provides a new perspective for deep research into solid-state LMBs.

Rationalizing Na-ion solvation structure by weakening carbonate solvent coordination ability for high-voltage sodium metal batteries

Commercial carbonate-based electrolytes feature highly reactive activities with alkali metals,yielding low Coulombic efficiencies and poor cycle life in lithium metal batteries,which possess much higher chemical activity in the rising star sodium metal batteries.To be motivated,we have proposed that decreasing the solvent solvation ability in carbonate-based electrolytes stepwise could enable longterm stable cycling of high-voltage sodium metal batteries.As the solvation capacity reduces,more anions are enticed into the solvation sheath of Na^(+),resulting in the formation of the more desirable interphase layers on the surface of the anode and the cathode.The inorganic-dominated interphases allow highly efficient Na^(+)deposition/stripping processes with a lower rate of dead sodium generation,as well as maintain a stable structure of the high-voltage cathode material.Specifically,the assembled Na||Na_(3)V_(2)(PO_(4))_(2)F_(3)battery exhibits an accelerated ion diffusion kinetics and achieves a higher capacity retention of 85.9%with during the consecutive 200 cycles under the high voltage of 4.5 V.It is anticipated that the tactics we have proposed could be applicable in other secondary metal battery systems as well.

Inverse-opal structured TiO_(2) regulating electrodeposition behavior to enable stable lithium metal electrodes

Lithium metal anode is almost the ultimate choice for high-energy density rechargeable batteries, but its uneven electrochemical dissolution-deposition characteristics lead to poor cycle stability and lithium dendrites safety problems. The fundamental solution to the problems is to interfere electrodeposition process of lithium metal so that it can be carried out reversibly and stably. In this work, an inverse-opal structured TiO2membrane with a thickness of only ~1 μm is designed to regulate the electrodeposition behavior of lithium metal, in which the ordered channels homogenize mass transfer process, the anatase TiO_(2)walls of the ion channels reduce desolvation barrier of solvated lithium-ions, and the spherical cavities with a diameter of ~300 nm confine migration of the adsorbed lithium atoms during electrocrystallization to diminish overpotential of lithium. These systematic effects cover and essentially change the whole process of electrodeposition of lithium metal and eliminate the possibility of lithium dendrite formation. The as-obtained lithium metal electrode delivers a Coulombic efficiency of 99.86% in the 100th cycle, and maintains a low deposition overpotential of 0.01 V for 800 h.

Dependence of lithium metal battery performances on inherent separator porous structure regulation

Boosting of rechargeable lithium metal batteries(LMBs) holds challenges because of lithium dendrites germination and high-reactive surface feature.Separators may experience structure-determined chemical deterioration and worsen Li plating-stripping behaviors when smoothly shifting from lithium-ion batteries(LIBs) to LMBs.This study precisely regulations the crystal structure of β-polypropylene and separator porous construction to investigate the intrinsic porous structure and mechanical properties determined electrochemical performances and cycling durability of LMBs.Crystal structure characterizations,porous structure analyses,and electrochemical cycling tests uncover appropriate annealing thermal stimulation concentrates β-lamellae thickness and enhances lamellae thermal stability by rearranging molecular chain in inferior β-lamellae,maximally homogenizing biaxial tensile deformation and resultant porous constructions.These even pores with high connectivity lower ion migration barriers,alleviate heterogeneous Li^(+) flux dispersion,stabilize reversible Li plating-stripping behaviors,and hinder coursing and branching of Li dendrites,endowing steady cell cycling durability,especially at higher currents due to the highlighted uncontrollable cumulation of dead Li,which offers new insights for the current pursuit of high-power density battery and fast charging technology.The suggested separator structure-chemical nature functions in ensuring cyclic cell stability and builds reliable relationships between separator structure design and practical LMBs applications.