Boosting kinetic separation of ethylene and ethane on microporous materials via crystal size control

The adsorptive separation of C_(2)H_(4)and C_(2)H_(6),as an alternative to distillation units consuming high energy,is a promising yet challenging research.The great similarity in the molecular size of C_(2)H_(4)and C_(2)H_(6)brings challenges to the regulation of adsorbents to realize efficient dynamic separation.Herein,we reported the enhancement of the kinetic separation of C_(2)H_(4)/C_(2)H_(6)by controlling the crystal size of ZnAtzPO_(4)(Atz=3-amino-1,2,4-triazole)to amplify the diffusion difference of C_(2)H_(4)and C_(2)H_(6).Through adjusting the synthesis temperature,reactant concentration,and ligands/metal ions molar ratio,ZnAtzPO4 crystals with different sizes were obtained.Both single-component kinetic adsorption tests and binary-component dynamic breakthrough experiments confirmed the enhancement of the dynamic separation of C_(2)H_(4)/C_(2)H_(6)with the increase in the crystal size of ZnAtzPO_(4).The separation selectivity of C_(2)H_(4)/C_(2)H_(6)increased from 1.3 to 98.5 with the increase in the crystal size of ZnAtzPO_(4).This work demonstrated the role of morphology and size control of adsorbent crystals in the improvement of the C_(2)H_(4)/C_(2)H_(6)kinetic separation performance.

Scattered Co-anchored MoS_(2)synergistically boosting photothermal capture and storage of phase change materials

Pristine phase change materials(PCMs)suffer from inherent deficiencies of poor solar absorption and photothermal conversion.Herein,we proposed a strategy of co-incorporation of zero-dimensional(OD)metal nanoparticles and two-dimensional(2D)photothermal materials in PCMs for efficient capture and conversion of solar energy into thermal energy.Highly scattered Co-anchored MoS_(2)nanoflower cluster serving as photon and phonon triggers was prepared by in-situ hydrothermal growth of ZIF67 polyhedron on 2D MoS_(2)and subsequent high-temperature carbonization.After encapsulating thermal storage unit(paraffin wax),the obtained composite PCMs integrated high-performance photothermal conversion and thermal energy storage capability.Benefiting from the synergistic enhancement of OD Co nanoparticles with localized surface plasmon resonance effect,carbon layer with the conjugation effect and 2D MoS_(2)with strong solar absorption,composite PCMs exhibited a high photothermal conversion efficiency of 95.19%,Additionally,the resulting composite PCMs also demonstrated long-term thermal sto rage stability and durable structu ral stability after 300 thermal cycles.The proposed collabo rative co-incorporation strategy provides some innovative references for developing next-generation photothermal PCMs in solar energy utilization.

Influence of grain refinement on the corrosion behavior of metallic materials:A review

Grain refinement can strengthen the mechanical properties of materials according to the classical Hall-Petch relationship but does not always result in better corrosion resistance.During the past few decades,various techniques have been dedicated to refining grain,along with relevant studies on corrosion behavior,including general corrosion,pitting corrosion,and stress corrosion cracking.However,the funda-mental consensus on how grain size influences corrosion behavior has not been reached.This paper reviews existing literature on the beneficial and detrimental effects of grain refinement on corrosion behavior.Moreover,the effects of microstructural changes(i.e.,grain boundary,dislo-cation,texture,residual stress,impurities,and second phase)resulting from grain refinement on corrosion behavior are discussed.The grain re-finement not only has an impact on the corrosion performance,but also results in microstructural changes that have a non-negligible effect on corrosion behavior or even outweigh that of grain refinement.Grain size is not the only factor affecting the corrosion behavior of metallic ma-terials;thus,the overall influence of microstructures on corrosion behavior should be understood.

Progress of electrochemical CO_(2)reduction reactions over polyoxometalate-based materials

Electrochemical CO_(2)reduction to value-added fuels and chemicals is recognized as a promising strategy to alleviate energy shortages and global warming owing to its high efficiency and economic feasibility.Recently,understanding the activity origin,selectivity regulation,and reaction mechanisms of CO_(2)reduction reactions(CO_(2)RRs)has become the focus of efficient electrocatalyst design.Polyoxometalates(POMs),a unique class of nanosized metal-oxo clusters,are promising candidates for the development of efficient CO_(2)RR electrocatalysts and,owing to their well-defined structure,remarkable electron/proton storage and transfer ability,and capacities for adsorption and activation of CO_(2),are ideal models for investigating the activity origin and reaction mechanisms of CO_(2)RR electrocatalysts.In this review,we focus on the activity origin and mechanism of CO_(2)RRs and survey recent advances that were achieved by employing POMs in electrocatalytic CO_(2)RRs.We highlight the significant roles of POMs in the electrocatalytic CO_(2)RR process and the main factors influencing selectivity regulation and catalytic CO_(2)RR performance,including the electrolyte,electron-transfer process,and surface characteristics.Finally,we offer a perspective of the advantages and future challenges of POM-based materials in electrocatalytic CO_(2)reduction that could inform new advancements in this promising research field.

Antioxidant Activity of 50 Traditional Chinese Medicinal Materials Varies with Total Phenolics

This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage.

Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method

Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a trend.The stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data method.The information on the corrosion process was recorded using the galvanic corrosion current monitoring method.The gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was investigated.Field exposure tests were conducted to verify the calculated results using the GBDT method.Results indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni steel.Dif-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of corrosion.When the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this rate.In the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion process.The corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection.

Fine-tuning electronic structure of N-doped graphitic carbon-supported Co-and Fe-incorporated Mo_(2)C to achieve ultrahigh electrochemical water oxidation activity

Mo_(2)C is an excellent electrocatalyst for hydrogen evolution reaction(HER).However,Mo_(2)C is a poor electrocatalyst for oxygen evolution reaction(OER).Herein,two different elements,namely Co and Fe,are incorporated in Mo_(2)C that,therefore,has a finely tuned electronic structure,which is not achievable by incorporation of any one of the metals.Consequently,the resulting electrocatalyst Co_(0.8)Fe_(0.2)-Mo_(2)C-80 displayed excellent OER catalytic performance,which is evidenced by a low overpotential of 214.0(and 246.5)mV to attain a current density of 10(and 50)mA cm^(-2),an ultralow Tafel slope of 38.4 mV dec^(-1),and longterm stability in alkaline medium.Theoretical data demonstrates that Co_(0.8)Fe_(0.2)-Mo_(2)C-80 requires the lowest overpotential(1.00 V)for OER and Co centers to be the active sites.The ultrahigh catalytic performance of the electrocatalyst is attributed to the excellent intrinsic catalytic activity due to high Brunauer-Emmett-Teller specific surface area,large electrochemically active surface area,small Tafel slope,and low chargetransfer resistance.

Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model

The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working conditions.Based on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were researched.Firstly,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution characteristics.The influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure area.Thirdly,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal.

STUDY ON Na_2O-GeO_2-SiO_2-PbO GLASSES USED AS THE CLADDING MATERIALS OF HOLLOW WAVEGUIDES FOR TRANSMITTING CO_2 LASER

In this paper a new kind of mid - infrared fiber material is reported. The reflective coefficients (R) of glasses in the system Na2O - ZnO - GeO2-SiO2-PbO have been measured-the refractive index becomes less than unity at 1180 - 900cm-1 range because of the existence of anomalous dispersion. The optical losses of hollow waveguides were calculated,the predicted losses at 940cm-1are 0. 65 and 0. 081B/ m as the inner diameter of fiber is 0. 5 and 1. 0mm respectively. The glasses can be used as the cladding materials of hol-low waveguides for transmitting CO2 laser from the measurements of characteristic temperatures, coefficient of expansion and chemical durability.

Erratum to: Influence of grain refinement on the corrosion behavior of metallic materials: A review

Erratum to:International Journal of Minerals, Metallurgy and MaterialsVolume 28, Number 7, July 2021, Page 1112 The original version of this article unfortunately contained mistakes. Symbols in Table 2 are used incorrectly.

Facile synthesis of accordion-like porous carbon from waste PET bottles-based MIL-53(Al)and its application for high-performance Zn-ion capacitor

It is of great scientific and economic value to recycle waste poly(ethylene terephthalate)(PET)into high-value PET-based metal organic frameworks(MOFs)and further convert it into porous carbon for green energy storage applications.In the present study,a facile and costeffective hydrothermal process was developed to direct recycle waste PET bottles into MIL-53(Al)with a 100% conversation,then the MOFderived porous carbon was assembled into electrodes for high-performance supercapacitors.The results indicated that the as-synthesized carbon exhibited high SSA of 1712 m^(2)g^(-1)and unique accordion-like structure with hierarchical porosity.Benefit to these advantageous characters,the assembled three-electrode supercapacitor displayed high specific capacitances of 391 F g^(-1)at the current density of 0.5 A g^(-1)and good rate capability of 73.6% capacitance retention at 20 A g^(-1)in 6 mol L^(-1)KOH electrolyte.Furthermore,the assembled zinc ion capacitor still revealed outstanding capacitance of 335 F g^(-1)at 0.1 A g^(-1),excellent cycling stability of 92.2% capacitance retention after 10000 cycles and ultra-high energy density of 150.3 Wh kg^(-1)at power density of 90 W kg^(-1)in 3 mol L^(-1)ZnSO_(4)electrolyte.It is believed that the current work provides a facile and effective strategy to recycle PET waste into high-valuable MOF,and further expands the applications of MOF-derived carbons for high-performance energy storage devices,so it is conducive to both pollution alleviation and sustainable economic development.

Dual-salt poly(tetrahydrofuran) electrolyte enables quasi-solid-state lithium metal batteries to operate at -30 ℃

The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)migration.Herein,we prepare a dual-salt poly(tetrahydrofuran)-based electrolyte consisting of lithium hexafluorophosphate and lithium difluoro(oxalato)borate(LiDFOB).The Li-salt anions(DFOB−)not only accelerate the ring-opening polymerization of tetrahydrofuran,but also promote the formation of highly ion-conductive and sustainable interphases on Li metal anodes without sacrificing the Li^(+)conductivity of electrolytes,which is favorable for Li^(+)transport kinetics at low temperatures.Applications of this polymer electrolyte in Li||LiFePO_(4)cells show 82.3%capacity retention over 1000 cycles at 30℃and endow stable discharge capacity at−30℃.Remarkably,the Li||LiFePO4 cells retain 52%of their room-temperature capacity at−20℃and 0.1 C.This rational design of dual-salt polymer-based electrolytes may provide a new perspective for the stable operation of quasi-solid-state batteries at low temperatures.

Mg/Fe site-specific dual-doping to boost the performance of cobalt-free nickle-rich layered oxide cathode for high-energy lithium-ion batteries

Layer-type LiNi0.9Mn0.1O2is promising to be the primary cathode material for lithium-ion batteries(LIBs)due to its excellent electrochemical performance.Unfortunately,the cathode with high nickel content suffers from severely detrimental structural transformation that causes rapid capacity attenuation.Herein,site-specific dual-doping with Fe and Mg ions is proposed to enhance the structural stability of LiNi0.9Mn0.1O2.The Fe3+dopants are inserted into transition metal sites(3b)and can favorably provide additional redox potential to compensate for charge and enhance the reversibility of anionic redox.The Mg ions are doped into the Li sites(3a)and serve as O_(2)^(-)-Mg^(2+)-O_(2)^(-)pillar to reinforce the electrostatic cohesion between the two adjacent transition-metal layers,which further suppress the cracking and the generation of harmful phase transitions,ultimately improving the cyclability.The theoretical calculations,including Bader charge and crystal orbital Hamilton populations(COHP)analyses,confirm that the doped Fe and Mg can form stable bonds with oxygen and the electrostatic repulsion of O_(2)^(-)-O_(2)^(-)can be effectively suppressed,which effectively mitigates oxygen anion loss at the high delithiation state.This dual-site doping strategy offers new avenues for understanding and regulating the crystalline oxygen redox and demonstrates significant potential for designing high-performance cobalt-free nickel-rich cathodes.

First‑principles study on electronic structure,optical and magnetic properties of rare earth elements X(X=Sc,Y,La,Ce,Eu)doped with two‑dimensional GaSe

The electronic structure,magnetic,and optical properties of two-dimensional(2D)GaSe doped with rare earth elements X(X=Sc,Y,La,Ce,Eu)were calculated using the first-principles plane wave method based on den-sity functional theory.The results show that intrinsic 2D GaSe is a p-type nonmagnetic semiconductor with an indi-rect bandgap of 2.6611 eV.The spin-up and spin-down channels of Sc-,Y-,and La-doped 2D GaSe are symmetric,they are non-magnetic semiconductors.The magnetic moments of Ce-and Eu-doped 2D GaSe are 0.908μ_(B)and 7.163μ_(B),which are magnetic semiconductors.Impurity energy levels appear in both spin-up and spin-down chan-nels of Eu-doped 2D GaSe,which enhances the probability of electron transition.Compared with intrinsic 2D GaSe,the static dielectric constant of the doped 2D GaSe increases,and the polarization ability is strengthened.The ab-sorption spectrum of the doped 2D GaSe shifts in the low-energy direction,and the red-shift phenomenon occurs,which extends the absorption spectral range.The optical reflection coefficient of the doped 2D GaSe is improved in the low energy region,and the improvement of Eu-doped 2D GaSe is the most obvious.

Constructing high-toughness polyimide binder with robust polarity and ion-conductive mechanisms ensuring long-term operational stability of silicon-based anodes

Silicon-based materials have demonstrated remarkable potential in high-energy-density batteries owing to their high theoretical capacity.However,the significant volume expansion of silicon seriously hinders its utilization as a lithium-ion anode.Herein,a functionalized high-toughness polyimide(PDMI) is synthesized by copolymerizing the 4,4'-Oxydiphthalic anhydride(ODPA) with 4,4'-oxydianiline(ODA),2,3-diaminobenzoic acid(DABA),and 1,3-bis(3-aminopropyl)-tetramethyl disiloxane(DMS).The combination of rigid benzene rings and flexible oxygen groups(-O-) in the PDMI molecular chain via a rigidness/softness coupling mechanism contributes to high toughness.The plentiful polar carboxyl(-COOH) groups establish robust bonding strength.Rapid ionic transport is achieved by incorporating the flexible siloxane segment(Si-O-Si),which imparts high molecular chain motility and augments free volume holes to facilitate lithium-ion transport(9.8 × 10^(-10) cm^(2) s^(-1) vs.16 × 10^(-10) cm^(2) s~(-1)).As expected,the SiO_x@PDMI-1.5 electrode delivers brilliant long-term cycle performance with a remarkable capacity retention of 85% over 500 cycles at 1.3 A g^(-1).The well-designed functionalized polyimide also significantly enhances the electrochemical properties of Si nanoparticles electrode.Meanwhile,the assembled SiO_x@PDMI-1.5/NCM811 full cell delivers a high retention of 80% after 100 cycles.The perspective of the binder design strategy based on polyimide modification delivers a novel path toward high-capacity electrodes for high-energy-density batteries.

Reduction of photodynamic damage of blood vessels in the protected region by(–)-epigallocatechin gallate

Photodynamic therapy(PDT)has been increasingly used in the clinical treatment of neoplastic,inflammatory and infectious skin diseases.However,the generation of reactive oxygen species(ROS)may induce undesired side effects in normal tissue surrounding the treatment lesion,which is a big challenge for the clinical application of PDT.To date,(–)-Epigallocatechin gallate(EGCG)has been widely proposed as an antiangiogenic and antitumor agent for the protection of normal tissue from ROS-mediated oxidative damage.This study evaluates the regulation ability of EGCG for photodynamic damage of blood vessels during hematoporphyrin monomethyl ether(Hemoporfin)-mediated PDT.The quenching rate constants of EGCG for the triplet-state Hemoporfin and photosensitized 1O2 generation are determined to be 6.8×10^(8)M^(−1)S^(−1),respectively.The vasoconstriction of blood vessels in the protected region treated with EGCG hydrogel after PDT is lower than that of the control region treated with pure hydrogel,suggesting an efficiently reduced photodamage of Hemoporfin for blood vessels treated with EGCG.This study indicates that EGCG is an efficient quencher for triplet-state Hemoporfin and 1O2,and EGCG could be potentially used to reduce the undesired photodamage of normal tissue in clinical PDT.

Pervaporation performance and characterization of hydrophilic ZSM-5 zeolite membranes for high inorganic acid and inorganic salts

The hydrophilic ZSM-5 zeolite membranes are applied to separate the inorganic acid solutions and inorganic acid/inorganic salt mixtures by pervaporation,and the membrane presents good stability,dehydration,and desalination performance.Influences of inorganic acid type(H_(2)SO_(4),H_(3)PO_(4),HNO_(3),and HCl),H_(2)SO_(4)concentration(1-6 mol·L^(-1)),test temperature(60-90℃)and inorganic acid/inorganic salt type(2 mol·L^(-1)H_(2)SO_(4)and sulfate,2 mol·L^(-1)H3PO4 and phosphate)on the pervaporation performance are investigated in this work.Either for concentrating 3%(mass)H_(2)SO_(4)solution or consecutive dehydrating 20%(mass)H_(2)SO_(4)solution,the hydrophilic ZSM-5 zeolite membrane has a good dehydration performance and stability.Even though the H_(2)SO_(4)concentration and test temperature are increased to 6 M and 90℃,only H_(2)O molecules could pass through the membrane and pH value of the permeation is kept neutral.Besides,the membrane has good dehydration and desalination performance for H_(2)SO_(4)/sulfates and H_(3)PO_(4)/phosphate mixtures,and the rejection of natrium salt,molysite,and magnesium is almost 100%.

Failure mechanisms and destruction characteristics of cemented coal gangue backfill under compression effect of non-uniform load

Backfill mining is one of the most important technical means for controlling strata movement and reducing surface subsidence and environmental damage during exploitation of underground coal resources. Ensuring the stability of the backfill bodies is the primary prerequisite for maintaining the safety of the backfilling working face, and the loading characteristics of backfill are closely related to the deformation and subsidence of the roof. Elastic thin plate model was used to explore the non-uniform subsidence law of the roof, and then the non-uniform distribution characteristics of backfill bodies’ load were revealed. Through a self-developed non-uniform loading device combined with acoustic emission (AE) and digital image correlation (DIC) monitoring technology, the synergistic dynamic evolution law of the bearing capacity, apparent crack, and internal fracture of cemented coal gangue backfills (CCGBs) under loads with different degrees of non-uniformity was deeply explored. The results showed that: 1) The uniaxial compressive strength (UCS) of CCGB increased and then decreased with an increase in the degree of non-uniformity of load (DNL). About 40% of DNL was the inflection point of DNL-UCS curve and when DNL exceeded 40%, the strength decreased in a cliff-like manner;2) A positive correlation was observed between the AE ringing count and UCS during the loading process of the specimen, which was manifested by a higher AE ringing count of the high-strength specimen. 3) Shear cracks gradually increased and failure mode of specimens gradually changed from “X” type dominated by tension cracks to inverted “Y” type dominated by shear cracks with an increase in DNL, and the crack opening displacement at the peak stress decreased and then increased. The crack opening displacement at 40% of the DNL was the smallest. This was consistent with the judgment of crack size based on the AE b-value, i. e., it showed the typical characteristics of “small b-value-large crack and large b-value-small crack”. The research results are of significance for preventing the instability and failure of backfill.

Boosting the catalytic activity toward oxygen reduction via a heterostructure of porous iron oxide-decorated 2D NiO/NG nanosheets

As a noble metal substitute,two-dimensional(2D)hierarchical nano-frame structures have attracted great interest as candidate catalysts due to their remarkable advantages-high intrinsic activity,high electron mobility,and straightforward surface functionalization.Therefore,they may replace Pt-based catalysts in oxygen reduction reaction(ORR)applications.Herein,a simple method is developed to design hierarchical nano-frame structures assembled via 2D NiO and N-doped graphene(NG)nanosheets.This procedure can yield nanostructures that satisfy the criteria correlated with improved electrocatalytic performance,such as large surface area,numerous undercoordinated atoms,and high defect densities.Further,porous NG nanosheet architectures,featuring NiO nanosheets densely coordinated with accessible holey Fe_(2)O_(3) moieties,can enhance mesoporosity and balance hydrophilicity.Such improvements can facilitate charge transport and expose formerly inaccessible reaction sites,maximizing active site density utilization.Density functional theory(DFT)calculations reveal favored O_(2) adsorption and dissociation on Fe_(2)O_(3) hybrid structures when supported by 2D NiO and NG nanomaterials,given 2D materials donated charge to Fe_(2)O_(3) active sites.Our systematic studies reveal that synergistic contributions are responsible for enriching the catalytic activity of Fe_(2)O_(3)@NiO/NG in alkaline media-encompassing internal voids and pores,unique hierarchical support structures,and concentrated N-dopant and bimetallic atomic interactions.Ultimately,this work expands the toolbox for designing and synthesizing highly efficient 2D/2D shelled functional nanomaterials with transition metals,endeavoring to benefit energy conversion and related ORR applications.