Structure Of Microspheres Research Articles

Activating the MnS0.5Se0.5 Microspheres as High-Performance Cathode Materials for Aqueous Zinc-Ion Batteries: Insight into In Situ Electrooxidation Behavior and Energy Storage Mechanisms.

Manganese-based materials are regarded as the most prospective cathode materials because of their high natural abundance, low toxicity, and high specific capacity. Nevertheless, the low conductivity, poor cycling performance, and controversial energy storage mechanisms hinder their practical application. Here, the MnS0.5Se0.5 microspheres are synthesized by a two-step hydrothermal approach and employed as cathode materials for aqueous zinc-ion batteries (AZIBs) for the first time. Interestingly, in-depth ex situ tests and electrochemical kinetic analyses reveal that MnS0.5Se0.5 is first irreversibly converted into low-crystallinity ZnMnO3 and MnOx by in situ electrooxidation (MnS0.5Se0.5-EOP) during the first charging process, and then a reversible co-insertion/extraction of H+/Zn2+ occurs in the as-obtained MnS0.5Se0.5-EOP electrode during the subsequent discharging and charging processes. Benefiting from the increased surface area, shortened ion transport path, and stable lamellar microsphere structure, the MnS0.5Se0.5-EOP electrodes deliver high reversible capacity (272.8mAhg-1 at 0.1Ag-1), excellent rate capability (91.8mAhg-1 at 2Ag-1), and satisfactory cyclic stability (82.1% capacity retention after 500 cycles at 1Ag-1). This study not only provides a powerful impetus for developing new types of manganese-based chalcogenides, but also puts forward a novel perspective for exploring the intrinsic mechanisms of in situ electrooxidation behavior.

Design of chlorella-inspired and smart-responsive bio-microspheres and their application in eco-friendly anti-biofouling coatings

Anti-biofouling coating materials have attracted much attention for their diverse functionality and extensive applications in various fields, such as marine facilities, biomedical apparatus, and so on. However, it is still a huge challenge for long-term anti-fouling coatings to improve the durability, safety, sustainability, eco-friendliness, and biodiversity. Herein, a novel biomimetic coating (Bio-OHMP coating) with eco-friendly and anti-biofouling performance was constructed on the basis of chlorella-inspired amino silicone oil (ASO)-core/polydopamine-shell bio-microspheres (Bio-OHMP microspheres). The Bio-OHMP microspheres were successfully fabricated through combining the hard/soft templates with high-stored hydrophobic substance. Similar to chlorella, great substance storage and delivery function were achieved for the Bio-OHMP microspheres, attributing to the larger central cavity structure of hollow mesoporous polydopamine microspheres (HMP microspheres) and the easy acquisition of NIR/Acid/Base smart-responsive self-healing properties of the Bio-OHMP microspheres. Superhydrophobic properties of the Bio-OHMP coating were originated from the hydrophobic and rough micro/nano-structured Bio-OHMP microspheres and nanoparticles. NIR/Acid/Base smart-responsive characteristics and long-termed superhydrophobic self-healing properties of the Bio-OHMP coating were gained due to the multiple-responsive Bio-OHMP microspheres, and the coating was endowed with high-efficient and large-scale healing abilities. Besides, great anti-biofouling abilities to typical biological or organic contaminants and long-period superhydrophobicity under harsh environments of the Bio-OHMP coating were all confirmed. This novel and multifunctional Bio-OHMP coating shows great prospects in anti-fouling, anti-adhesion, or other fields, while the chlorella-inspired Bio-OHMP microspheres have great potentials to be applied to other functionalized materials.

High efficiency toluene sensor based on iron-doped nickel oxide triple-shell microspheres with high moisture resistance

This paper provides a simple one-step synthesis of Fe-doped NiO triple-shell layer microsphere structures for toluene gas detection. The 2 at% Fe-doped NiO sensor has excellent sensing ability for toluene gas, with high response (36–100 ppm), low detection limits (100 ppb), fast response and recovery time (2/20 s). Moreover, the sensor demonstrates excellent moisture resistance, with satisfactory response to toluene even in conditions of 99 % relative humidity (34.1–100 ppm). To further investigate the adsorption properties of the sensor, a density functional theory (DFT) approach was employed, and the sensing mechanism of the NiO sensor was discussed detailly. Analysis of the results suggests that Fe-doped NiO triple-shell layer microspheres represent a promising approach for the design of high-performance toluene gas sensors.

Insight into the Li-Storage Property of Surface-Modified Ti2Nb10O29 Anode Material for High-Rate Application.

Ti-based anode materials are considered to be an alternative to graphite anodes to accomplish high-rate application requirements. Ti2Nb10O29 (TNO15) has attracted much attention due to its high lithium storage capacity through the utilization of multiple redox couples and a suitable operating voltage window of 1.0 to 2.0 V vs Li/Li+. However, poor intrinsic electronic conductivity has limited the futuristic applicability of this material to the battery anode. In this work, we report the modification of TNO15 by introducing oxygen vacancies and using few-layered carbon and copper coatings on the surface to improve its Li+ storage property. With the support of the galvanostatic intermittent titration technique (GITT), we found that the diffusion coefficient of carbon/copper coated TNO15 is 2 orders of magnitude higher than that of the uncoated sample. Here, highly conductive copper metal on the surface of the carbon-coated oxygen-vacancy-incorporated TNO15 increases the overall electronic and ionic conductivity. The prepared TNO15-800-C-Cu-700 half-cell shows a significant rate capability of 92% when there is a 10-fold increase in the current density. In addition, the interconnected TNO15 nanoparticles create a porous microsphere structure, which enables better Li-ion transportation during charge/discharge process, and experiences an enhancement after the carbon and copper coating on the surface of the primary TNO15 nanocrystallites.

Crystallization-driven formation poly (l-lactic acid)/poly (d-lactic acid)-polyethylene glycol-poly (l-lactic acid) small-sized microsphere structures by solvent-induced self-assembly

Improving hydrophobicity through the regulation of surface microstructures has attracted significant interest in various applications. This research successfully prepared a surface with microsphere structures using the Non-solvent induced phase separation method (NIPS). Poly(D-Lactic acid)-block-poly(ethylene glycol)-block-poly(D-Lactic acid) (PDLA-PEG-PDLA) block polymers were synthesized by ring-opening polymerization of D-Lactic acid (D-LA) using polyethylene glycol (PEG) as initiator. PLLA/PDLA-PEG-PDLA membrane with microscale microsphere morphology was fabricated using a nonsolvent-induced self-assembly method by blending the triblock copolymer with a poly(L-lactic acid) (PLLA) solution. In phase separation processes, the amphiphilic block copolymers self-assemble into micellar structures to minimize the Gibbs free energy, and the hydrophilic segments (PEG) aggregate to form the core of the micelles, while the hydrophobic segments (PDLA) are exposed on the outer corona resulting in a core-shell structure. The Stereocomplex Crystalline (SC), formed by the hydrogen bonding between PLLA and PDLA, can facilitate the transition from liquid-liquid phase separation to solid-liquid phase separation, and the PEG chain segments can enhance the formation of SC. The membrane, prepared by adjusting the copolymer content and PEG chain length, exhibited adjustable microsphere quantity, diameter, and surface roughness, enabling excellent hydrophobicity and controlled release of oil-soluble substances.

Thermal Characteristics and Temperature Distribution of Asphalt Mixtures Containing Residues from Municipal Solid Waste Incineration

As a sustainable substitute for non-renewable mineral resources and solid waste landfilling, municipal solid waste incineration residues (MSWIRs) are useful in road pavements. This study investigates the thermal characteristics and temperature distribution of flexible pavements containing MSWIRs with hollow microsphere structures. First, the volumetric properties of asphalt mixtures containing MSWIR fillers were measured. The effects of MSWIRs on the mixture’s physical characteristics were investigated in terms of thermal conductivity, specific heat capacity, and thermal diffusivity. A three-dimensional finite element model incorporating surface thermal conditions was established and validated to analyze the internal temperature distribution and heat transfer behavior within the asphalt. Finally, the high-temperature conditions of summer were simulated in an indoor irradiation test to evaluate the risk of heat islands in urban areas. The results showed that the mixture containing MSWIRs exhibited a higher specific heat capacity (from 0.8385 to 0.9554 J/(kg·K)) and lower thermal conductivity (from 1.4356 to 1.1362 W/(m·K)) than the reference mixture with limestone filler. Therefore, it contributed to a lower heat flux distribution within the pavement. However, the increase in asphalt surface temperature caused by MSWIRs may exacerbate the urban heat island effect in the summer, which should be considered before using road materials containing MSWIRs.

NiS2 @MWCNTs as a promising anode material for lithium and sodium-ion batteries with superior cycling stability

The NiS2 @MWCNTs materials were synthesized using a straightforward hydrothermal one-step process, forming a 3D conductive network structure with stable and uniformly distributed nanosphere morphology. Electrochemical tests yielded a sodium storage capacity of 463.99 mAh g−1 after 400 cycles with 0.2 A g−1, and a coulomb efficiency of 83.3% at the first cycle, followed by excellent long-cycle stability with a capacity retention rate of 96.7% after 600 cycles at a high current of 1 A g−1. It's interesting to note that Na+ storage mechanism is provided by a pseudocapacitor. The 3D conductive network was credited with enhanced electrochemical performance and structural stability. The incorporation of multi-walled carbon nanotubes (MWCNTs) also improves the material conductivity and accelerated the ion transport efficiency, while modulation of the nano microsphere structure increases the reactive active sites and reduce the capacity loss. These findings highlight the great potential NiS2 @MWCNTs composites as a perfect anode material for sodium-ion batteries (SIBs), opening up new possibilities for sustainable energy storage solutions.

Synthesis of fractal crystallized organic microspheres together with constructing full covalent bonding at the interface to strengthen and toughen aramid fiber composites

Regulating the interface to simultaneously enhance the strength and toughness of aramid fiber composites remains a great challenge. Herein, a resilient, full covalent interface was constructed by introducing fractal crystallized organic microspheres into the interface of aramid fiber composites using the twice fluorination approach. Firstly, the aromatic polyamide with ether bonds was synthesized, and the fractal crystallized microspheres with a porous surface containing amino groups were prepared by thermally induced solution self-assembly. Subsequently, the twice fluorination method introduces C–F bonds to the surfaces of both fibers and microspheres, respectively. Then, the covalent bonds among fibers, microsphere, and resin were formed by the derivative reaction of C–F bonds. This interface boosts the interlaminar shear strength (ILSS) of composites by 100.5% to 36.7 MPa and the unnotched impact toughness of composites by 13.5%–1363 kJ/m2. Comparative analyses reveal the full covalent interface and the fractal structure of microspheres contribute 47.8% and 52.2% to the ILSS enhancement, respectively. In addition, the fractal structure of microspheres is the only factor for increased toughness. Finite element analysis reveals that the fractal crystallized microspheres combined with full covalent interface facilitate elastic stress transfer within the composites to enhance the performance of composites.

Preparation of DOPO-KH550 modified hollow glass microspheres/PVA composite aerogel for thermal insulation and flame retardancy

The creation of high-performance thermal insulation and flame-retardant materials is of great importance for minimizing energy consumption and reducing fire risk for modern buildings. Herein, we report the creation of a new composite aerogel, which was prepared by incorporation of 9,10-Dihydro-9-oxa-10-phosphaphenanthrene 10-Oxide-3-Aminopropyl triethoxysilane (DOPO-KH550) modified hollow glass microspheres (HGM) into polyvinyl alcohol (PVA) using citric acid as a cross-linker, as a kind of thermal insulation and flame retardant materials (abbreviated as PVA-DKHGM). The as-synthesized PVA-DKHGM composite exhibits superior thermal conductivity of 0.0187 W m−1 K−1, owing to the hollow structure of the hollow glass microspheres and rich porosity. Besides, it reaches V-0 level at the UL-94 test and the peak heat release rate (pHRR) was measured to be 114.93 (kW/m2) which is lower than most composites now. These results are attributed to the synergy effect of the hollow glass microsphere and DOPO-KH550 which offers the composites aerogel excellent flame retardancy. Owing to its advantages such as lightweight, highly porous, thermally stable, simple to prepare, high mechanical strength, and can be further scaled up, our PVA-DKHGM aerogel may hold great potential for practical applications in construction of energy-saving modern buildings.

Unveiling a cutting-edge bi-ligand nickel metal-organic framework as an electrode material for symmetric supercapacitors

Perylene diimide (PDI)-based MOFs feature a substantial specific capacitance, terrific cycle durability, swift charge/discharge rates, exceptional chemical as well as thermal endurance, diversity in electrode design, and inexpensive production costs. In light of these benefits, PDI-based MOFs are intriguing options for utilization in energy storage. Inspired by the distinctive features of perylene diimide-based ligands, highly conjugated and nitrogen-rich organic ligands Perylene diimide-L-dopa (PDI-L-Dopa) were incorporated to create the Ni-MOF architecture. The resulting hierarchical flower-like microspheres of bi-ligand Ni-MOF had better electron transport, conductivity, and wettability. When applied as electrode material in a three-electrode system considering a specific capacitance of 198 F/g at a current density of 1 A/g, the Ni-MOF-24 h electrode showcased beneficial electrochemical efficiency. XRD, FT-IR, and XPS were used to validate the formation of Ni-MOF and disclose the exact chemical composition and valence state inside the material. The hierarchical flower-like microsphere structure of the Ni-MOF, formed of 2D petal-like nanosheets, was revealed by FE-SEM and TEM. Additionally, when Ni-MOF-24 h electrodes used to fabricate symmetric supercapacitor (SSC), it reveals a high energy density (Ed) of 23 Wh/kg at a corresponding power density (Pd) of 600 W/kg along with extraordinary cyclic stability over 10,000 charge/discharge cycles with retaining 99 % of the initial capacitance. This research sheds light on the design and manufacture of innovative materials for long-term and efficient energy storage devices based on MOFs.

3D printed composites achieve broadband electromagnetic wave absorption by introducing carbon black/carbonyl iron powder porous hollow microspheres

In this paper, carbon black (CB) and carbonyl iron powder (CIP) were successfully combined by solvent evaporation method to prepare CB-CIP porous hollow microspheres and used as reinforcement to prepare electromagnetic wave absorbing composites by 3D printing method. The effects of CB addition on the structure of the composite microspheres and the wave absorption performance were investigated. It is shown that the surfaces of hollow microspheres have many heterogeneous interfaces and pore defects, which can significantly enhance the polarization loss capability. The CB and CIP particles on the surfaces of hollow microspheres are intertwined, which makes the magnetic loss and dielectric loss form a synergistic absorption effect and enhance the microwave absorption capacity of the composite. The maximum reflection loss of sample CB/PLA-3 reaches –47.34 dB at a thickness of 2.5 mm, and the EAB is 4.56 GHz. The EAB reaches a maximum of 5.20 GHz at a thickness of 2 mm. The RCS simulation results of CB/PLA-3 at 11 GHz show that most of the RCS values of the samples are below −20 dBm2 in the range of –90° < Theta < 90°, indicating that the CB/PLA-3 samples has the capability of wide-angle microwave absorption. This paper provides an effective method for the design and preparation of broadband efficient absorbing materials.

Preparation of cassava starch-gelatin yolk-shell microspheres by water-in-water emulsion method

This paper reports the preparation and characterization of gelatin-cassava starch microspheres using the water-in-water emulsion technique. The effects of different weight ratios (10: 0, 9: 1, 8: 2, 7: 3, 6: 4, 5: 5) of starch to gelatin on the morphology, structure, thermal properties, and stability of microspheres were investigated. The morphology results showed that most microspheres had spherical shapes and smooth surfaces. When the weight ratio of starch to gelatin was 5: 5, the prepared microspheres formed a stable yolk-shell structure. The swelling capacity of the microspheres increased with the proportion of gelatin, up to 682.3 %. The gelatin and starch in the microspheres were compatible but not miscible. Compared with the native starch, the crystalline structure of microspheres changed from A-type to a mixture of B-type and V-type, and the relative crystallinity decreased. Differential scanning calorimetry results showed that the melting of microspheres involved both gelatin dissolution and starch gelatinization. Due to the formation of composite microspheres, the starch content decreased, and the release of reducing sugars from the microspheres upon hydrolysis was reduced. The gelatin-cassava starch microspheres are simple to prepare, biocompatible, and can be used as a potential material for microencapsulation.

Amorphous TiO2 doped with carbon for visible light photocatalytic oxidation of elemental mercury

A novel simple sol–gel method, flame assisted fabrication of amorphous TiO2 doped with carbon, was demonstrated. The as-prepared samples were identified by TGA, XRD, SEM and BET. And the optical property of the as-prepared samples was measured by the UV–vis and FTIR. The obtained amorphous C-TiO2 (carbon-doped TiO2) photocatalysts were used to remove gaseous elemental mercury under visible light (LED) and the optimum doping levels of C-TiO2 were determined. The results show that all the samples had a good mercury removal efficiency (>50 %). When the volume ratio of TBOT/ethanol reached 1:13, the sample has the best mercury removal efficiency 76 %. The incorporation of carbon and the microspherical structure enhanced the ability of light absorption, which led to the improvement of photocatalytic activity. This work has proposed the probable mechanism of removing gaseous elemental mercury by amorphous C-TiO2.

Glutamic based self-assembly urchin microsphere structure metal organic framework for gas sorption and aluminium ion sensing applications

Bio-molecules based self-assembled nano range metal-organic frameworks (MOFs) potential materials used in recent compact applications. For its structural tunability, large void area, pore volumes and eco-friendly nature. In this work, we report the same composition but different synthesized method glutamic acid cobalt node-based metal-organic compounds GACo1 and GACo2. In this material, GACo2 has the property of a nanocrystalline nature, this fundamental combination forms self-assembly uniform well-developed porous 3D urchin-like microsphere architectures with the dimension of 1.5 µm. The sorption analysis declares N2 adsorbed in the amount of 1544 ccg−1 and surface area is 2695 m2 g−1 without supercritical CO2 treatment. Interestingly, GACo2 MOF acts as a fluorescence probe for Al3+ metal ions in the aqueous phase with high selectivity and sensitivity. The KSV value and detection limit of material were 2.13 × 103 M−1 and 0.0547 × 10−7 M respectively, Also, the limit of detection is significantly lower than the WHO recommendation of Al3+ ion for drinking water ((7.41310−3 M)). Interestingly, the turn-on-sensing ability of GACo2 MOF for Al3+ ions in an aqueous medium was achieved even in the presence of a change in the pH of the solution.

Highly sensitive and selective Sb2WO6 microspheres in detecting VOC biomarkers in cooked rice: Experimental and density functional theory study.

The palatability of cooked rice is susceptible to the flavor and effective detection of volatile organic compounds (VOCs) can avoid deterioration and improve the taste quality. Herein, hierarchical antimony tungstate (Sb2WO6) microspheres are synthesized through a solvothermal process and the effect of solvothermal temperature on the room temperature gas-sensing properties of gas sensors is investigated. Outstanding sensitivity towards VOC biomarkers (nonanal, 1-octanol, geranyl acetone and 2-pentylfuran) in cooked rice is achieved and the sensors exhibit remarkable stability and reproducibility, which are contributed to the formation of the hierarchical microsphere structure, larger specific surface area, narrower band gap and increased oxygen vacancy content. The kinetic parameters combined with principal component analysis (PCA) effectively distinguish the four VOCs while the enhanced sensing mechanism was substantiated through density functional theory (DFT) calculation. This work provides a strategy for fabricating high performance Sb2WO6 gas sensors which can be practically applied to food industry.

Porous Fe1-xS/C microspheres constructed by L-aspartic acid as high-performance anode material for lithium-ion batteries

Porous microspherical structure for metal oxides or sulfides as anode material exhibits dramatic advantages in improving electrochemical properties of lithium-ion batteries (LIBs). Herein, porous Fe1-xS microspheres with uniform size were synthesized through a hydrothermal reaction where L-aspartic acid molecules guide crystal growth and form secondary particles. The microsphere with perforated channels provides facile channels for the migration of Li+ and accommodates mechanical stress to suppress volume expansion. The residual carbon decomposed from the L-aspartic acid molecules in the final composite also facilitates the electron transfer and prevents polysulfides from dissolving into electrolyte. Thus, the Fe1-xS/C maintains superior structural stability in a long cycling with excellent reversible capacity at high rates. Specifically, the Fe1-xS/C electrode deliverers a capacity of 534 mAh g−1 at 20 A g−1 and lefts 810 mAh g−1 after 3000 cycles at 5 A g−1.

Insight into the Structure of MOF-Containing Hybrid Polymeric Microspheres.

Polymer science exploited metal organic frameworks (MOFs) for various purposes, which is due to the fact that these materials are ideal platforms for identifying design features for advanced functional materials. The mechanism of polymerization using MOFs, is still largely unexplored and the detailed characterization of both materials in essential to understand the important interactions between the components. In this work modern advanced research methods were used to investigate the properties of MOF-containing hybrid polymeric microspheres. Hydrothermal conversion of CFA-derived iron particles was used to obtain MOF nanostructures, which were then introduced to the structure of hybrid polymer microspheres based on ethylene glycol dimethylacrylate (EGDMA) and triethoxyvinylsilane (TEVS). Chemical structures were confirmed by ATR-FTIR method. To provide information about the elemental composition of the tested materials and for the determination of chemical bonds present in the tested samples XPS method was applied. Morphology was studied using SEM microscopy, whereas porosity was investigated using ASAP technique. Swellability coefficients were determined using typical organic solvents and distilled water. Moreover, the ecological aspect concerning the use of fly ashes deserves to be emphasized.

Design and development of Carissa edulis fruit extract mediated bimetallic CuO-NiO-HNT composites for photocatalytic removal of food dye and antibiotic drug

The current study demonstrates the synthesis of one dimensional halloysite nanotube (HNT) based CuO-NiO (CN) photocatalyst using green approach via non-conventional microwave and ultrasonication method. Structural, optical, electrochemical, morphological, stability, and surface area characteristics of the synthesised composite were investigated. From the optical studies, the composite exhibited the absorption band edge above 420 nm in the visible region. Electrochemical studies confirmed that 20CN-HNT composited had good charge carrier separation rate compared to CN. Morphological and elemental analysis revealed that the composite was in microsphere structure with even distribution of elements throughout the composite. Congo red (CR- a dye) and tetracycline (TC- a drug) were used to test the composites' photocatalytic efficacy by the irradiation of visible light. Amongst various synthesized composites, 20CN-HNT composite showed good removal efficiency around 82 % and 84 % against CR and TC respectively, in 90 min. The breakdown of CR and TC is caused by the active species •OH and •O2– radicals which was identified using trapping studies. The reusability study demonstrated that the 20CN-HNT photocatalyst retained its high level of stability after being used for five times.

Fe-Ni bimetallic adsorbent for efficient As2O3 removal from coal-fired flue gas under a wide temperature range: Experimental and DFT study

Adding metal oxides in the furnace can effectively control the emission of heavy metal arsenic in the coal-fired flue gas, and α-Fe2O3 has excellent adsorption performance. However, single metal oxides still have defects such as easy sintering or weak oxidation ability during use, which significantly impact the adsorption effect of arsenic. In this work, a new Fe-Ni bimetallic adsorbent was prepared by hydrothermal calcination, and its mechanism of As2O3 adsorption was investigated in depth through the combination of experiment and theory. The experimental results show that the FN8 (Ni-doped molar percentage is 8%) adsorbent exhibits excellent performance, and its arsenic adsorption capacity reaches 405.60 mg/kg, which is more than twice the adsorption capacity of α-Fe2O3. Ni doping can not only regulate the electron transfer between the α-Fe2O3 interface and As, but also promote the conversion of lattice oxygen to chemisorbed oxygen in the system. In the temperature range of 500 °C–900 °C, the prepared FN8 adsorbent can maintain a good microsphere structure, avoid sintering and provide more adsorption sites, and its arsenic capture capacity is stronger than α-Fe2O3. The density functional theory further reveals the microscopic mechanism of improving the oxidation performance of Fe-Ni adsorbent. The results show that Fe-Ni adsorbent has lower adsorption energy than α-Fe2O3. This is due to the synergism of Ni and O, which leads to the redistribution of electrons on the α-Fe2O3 (001) surface, and the Ni atom provides more free electrons for O atoms, which ultimately promotes the oxidation ability of Fe-Ni adsorbent and forms an As-O covalent bond. The Fe-Ni bimetallic composite adsorbent proposed in this work provides a new idea of bimetallic adsorbent for the effective adsorption of arsenic in the flue gas.

MXene@Co hollow spheres structure boosts interfacial polarization for broadband electromagnetic wave absorption

MXene is considered as a candidate for preparing high-performance electromagnetic wave absorbing materials due to its large specific surface area, rich surface modification groups, and unique metal properties. However, the impedance matching problem caused by its high conductivity and easy stacking properties is a limiting factor. In this study, a self-assembling-etching-anchoring growth method was proposed to prepare MXene@Co electromagnetic wave absorbing materials. The hollow structure of MXene microspheres constructed with PMMA as a hard template is conducive to optimizing impedance matching and surface modification. In addition, MXene@Co exhibits abundant heterogeneous interfaces, enhancing the interfacial polarization phenomenon during electromagnetic wave absorption. Meanwhile, the surface-anchored growth of magnetic Co particles forms a magnetic network, which provides a strong magnetic loss capability for the absorber. The hollow structure design significantly enhances the wave absorption performance compared to conventional MXene@Co composites, with a minimum reflection loss of −57.32 dB (effective absorption bandwidth of 5.2 GHz) when the thickness is 2.5 mm (2.2 mm). This work provides a meaningful reference for the design of MXene-based electromagnetic wave absorbing materials.