Porous MXene Research Articles

Bimetal anchoring porous MXene nanosheets for driving tandem catalytic high‐efficiency electrochemical nitrate reduction

AbstractElectrochemical nitrate reduction reaction (NO3RR) is considered a promising strategy for ammonia synthesis and nitrate removal, in which catalyst development is crucial. Herein, a series of bimetal (Co and Cu) anchoring porous MXene nanosheets (CoxCuy@PM) catalysts were prepared by combining etching and reduction strategy. On the one hand, Cu and Co bimetals provided tandem catalytic active sites for NO3RR. On the other hand, the in‐plane PM exhibited good electrical conductivity and multiple transport pathways. Consequently, the optimized Co7Cu3@PM catalyst achieved a high ammonia yield of 7.43 mg h−1 mg cat.−1 and an excellent Faraday efficiency (FE) of 95.9%. The mechanism of NO3RR was investigated by analyzing electrolysis products and in situ Fourier transform infrared spectroscopy. Furthermore, the Co7Cu3@PM based ZnNO3− battery exhibited the superior power density of 5.59 mW cm−2 and an NH3 FE of 92.3%. This work presents an effective strategy to design MXene‐based high‐performance NO3RR electrocatalysts.

Electrochemical/fluorescent dual-mode aptasensor based on 3D porous AuNPs/MXene for detection of ultra-trace mercury (Hg2+)

In this work, the dual-mode aptasensor based on 3D porous AuNPs/MXene using “turn-on” electrochemical method and “turn-off” fluorescent strategy was fabricated. Here, 2D MXene was processed into 3D porous MXene by sacrificial polymethylmethacrylate (PMMA) spherical template. And the meteor hammer-like AuNPs which had good electrochemical properties and quenching effect on fluorescence was synthesized by single electrodeposition. Dual-signal labeled Nile Blue (NB) was in situ grafted to the Hg2+ aptamer ends of 3D porous AuNPs/MXene/GCE, and an efficient and sensitive signal interface was constructed to realize the sensitive detection of Hg2+. 3D porous AuNPs/MXene had the advantages of large specific surface area, excellent electron transmission performance and signal amplification. The experimental results indicated that this sensor exhibited high sensitivity to Hg2+ in both electrochemical and fluorescent sensing, with detection limits of 2.69 fM and 1.60 fM, respectively. Further, the dual-mode aptasensor can ensure the detection accuracy and target quantization. The dual-mode aptasensor has been successfully applied to the ultra-trace detection of Hg2+ in actual water samples, which shows the potential of aptamer sensor in detecting heavy metal ions in environmental monitoring.

Hierarchical porous MXene film with diffusion path optimization for supercapacitor

MXenes have immense potential in electrochemical energy storage owing to their outstanding physicochemical properties such as their oxygen-containing groups that impart additional pseudocapacitance to acidic electrolytes. However, during electrode assembly, MXene nanosheets undergo restacking because of hydrogen bonding and van der Waals forces, which causes electrolyte ions to traverse long diffusion pathways between the long and narrow nanosheets. Exploiting the oxidative properties of Ti3C2Tx, a hierarchical porous MXene film with micro-, meso- and macroporous structures was successfully prepared using a simple hydrothermal oxidation and etching process to create micro- and mesoporous structures, followed by ice templating to prepare three-dimensional (3D) linked macroporous structures. Because these hierarchical pores have synergistic effects on electrochemical activity and electrolyte ion diffusion, the film attained a specific capacitance of 539F/g at a current density of 2 A/g when it was used as a supercapacitor electrode, which corresponds to one of the highest values reported for MXene-based electrodes. The film retained 83% of its specific capacitance when the current density was increased to 40 A/g, and exhibited excellent cycling stability. By using this multi-porous MXene design, synergistic improvement in ion diffusion was successfully realized and thus a new strategy to prepare high-performance supercapacitor electrode materials was developed.

A smartphone-assisted ultrasensitive colorimetric aptasensor based on DNA-encoded porous MXene nanozyme for visual detection of okadaic acid

The smartphone-assisted ultrasensitive colorimetric aptasensor based on DNA-encoded porous Ti3C2 nanozyme (Apt-P-Ti3C2) was exploited for real-time detection of OA. Porous Ti3C2 (P-Ti3C2) MXene with outstanding peroxidase-like activities were crafted using microwave combustion, facilitating the efficient catalysis of chromogenic substrate oxidation by H2O2. The integration of a considerable number of unsaturated Ti center edges and residual Mn2+ within the single-layer porous Ti3C2 framework augmented the adsorption capacity of DNA aptamer, thereby yielding a heightened catalytic efficacy of P-Ti3C2 nanoparticles. The enhanced catalytic activity of P-Ti3C2 can be partially diminished through specific recognition of OA. Concurrently, a smartphone platform was integrated for signal reading based on the colorimetric sensing strategy. The smartphone-based biosensor exhibited a reliable and ultrasensitive capability for OA detection with the detection limit of 0.38 ng·mL−1. It is anticipated that the developed smartphone-based biosensing platform can provide a prospective ultrasensitive detection method for marine algal toxin in food analysis.

Oxygen-rich 3D hierarchical porous MXene prepared by Zn powder reduction for flexible supercapacitors

Ti3C2Tx MXene is highly compelling as an energy storage material, but 2D MXene sheets experience significant stacking due to hydrogen bonding and van der Waals forces. This blocks active sites and impedes fast electrolyte ion transport. The pseudocapacitance of MXene materials is highly reliant on their terminal groups. Therefore, an effective strategy was designed herein to prepare an oxygen-rich 3D hierarchical porous MXene (P-OR-Ti3C2Tx). First, Zn powder was used as a template to construct three-dimensional hierarchical porous structures that spanned the microporous, mesoporous, and macroporous scales. Second, Zn powder was used as a metal reducing agent in a reaction at 500 °C to eliminate most −F terminal groups on the MXene. Then, a subsequent acid washing step was used to introduce numerous −O terminal groups. The energy storage process of the prepared MXene was investigated by in situ Raman. More redox active sites (−O terminal groups) are exposed by the constructed oxygen-rich 3D hierarchical porous MXene structure, which also provides a shorter pathway for electrolyte ion transport. P-OR-Ti3C2Tx displays superb rate performance (88.19 % retention at 100Ag−1) and ultra-high capacitance (676.7F/g at 2 mV/s and 698.7Fg−1 at 1 Ag−1) when used as a supercapacitor electrode. Moreover, a symmetric flexible supercapacitor device prepared using P-OR-Ti3C2Tx and carbon cloth achieves a superb energy density of 32.8Whkg−1 at a power density of 236.5Wkg−1. This study offers insight into the design of MXenes that exhibit both high capacity and excellent rate performance.

Double cross-linking system for constructing tortuosity-lowered and strength-enhanced porous MXene films with superior capacitive performance and electromagnetic shielding efficiency

Porous MXene films are ideal materials for flexible electronics because of their various porous structures and rich surface chemistry. However, the typical problem, especially as flexible supercapacitors, is that MXene lamellae are still prone to stacking. Many channels are disconnected from each other, facing high ion transport resistance. Herein, an optimal 3D structure is built by ion-molecular double cross-linking system and subsequent freeze-casting with lowered-tortuosity and enhanced-strength for porous MXene films. Ionic cross-linking is used to adjust the orientation of the MXene lamellae by coulombic attraction, while optimized terminal and ion intercalation widens the layer spacing. Molecular cross-linking is used to adjust the backbone of the porous structure through hydrogen bonding interactions. As a result, due to the porous structure of connectivity, the porous MXene-OH/BC (MOB) delivers a capacitance of 527 F g-1, mechanical property of 41.5 MPa (140 % and 367 % of the MXene film, respectively), and the shielding efficiency of 67.2 dB (X-bond). In addition, the assembled NAC//MOB device achieves high energy density of 56.28 Wh kg-1 and 85.6 % capacitance retention after 50,000 cycles. This work shows a well-designed porous film with lightweight, flexible and strong mechanical properties, expanding the competitiveness of MXene materials for real-world applications.

Biomimetic Porous MXene Antibacterial Adsorbents with Enhanced Toxins Trapping Ability for Hemoperfusion.

2D transition metal carbides and nitrides, i.e., MXene, are recently attracting wide attentions and presenting competitive performances as adsorbents used in hemoperfusion. Nonetheless, the nonporous texture and easily restacking feature limit the efficient adsorption of toxin molecules inside MXene and between layers. To circumvent this concern, here a plerogyra sinuosa biomimetic porous titanium carbide MXene (P-Ti3C2) is reported. The hollow and hierarchically porous structure with large surface area benefits the maximum access of toxins as well as trapping them inside the spherical cavity. The cambered surface of P-Ti3C2 prevents layers restacking, thus affording better interlaminar adsorption. In addition to enhanced toxin removal ability, the P-Ti3C2 is found to selectively adsorb more middle and large toxin molecules than small toxin molecules. It possibly originates from the rich Ti-deficient vacancies in the P-MXene lattice that increases the affinity with middle/large toxin molecules. Also, the vacancies as active sites facilitate the production of reactive oxygen under NIR irradiation to promote the photodynamic antibacterial performance. Then, the versatility of P-MXene is validated by extension to niobium carbide (P-Nb2C). And the simulated hemoperfusion proves the practicability of the P-MXene as polymeric adhesives-free adsorbents to eliminate the broad-spectrum toxins.

Ultrasensitive and highly selective NO2 gas sensing of porous MXene nanoribbon assemblies

Nitrogen dioxide (NO2), a potential source for acid rain and photochemical smog, is known to harm human health, plant growth and crop yield, and the environment. Therefore, designing a room temperature operable NO2 gas sensor with exceptional sensitivity and selectivity is extremely important. Herein, we report that Ti3C2Tx MXene (Tx = –OH, –O, –F, etc.) nanoribbons containing inbuilt anatase TiO2 on their surfaces achieve highly sensitive detection of NO2 gas at room temperature with negligible cross-responses to other gas analytes. The MXene nanoribbons' ability to form porous gas sensor film facilitates the efficient diffusion of gas molecules and the sufficient utilization of surface-active sites, leading to a high response of −87.5 % to 50 ppm NO2 gas exposure with a response time of 9.2 s at room temperature. Signifying the low concentration NO2 detection abilities, MXene nanoribbons displayed a response of −4.4 % towards 500 ppb NO2 exposure. MXene nanoribbons' NO2 gas sensing ability is carrier gas dependent and declines monotonically as operating temperature increases. In addition, the performance comparison experiments conducted at 50 ppm NO2 gas exposure suggest that the MXene nanoribbons' response is 14.3, 1.6, and 45.3 times higher than the responses of multilayer MXene, MXene-TiO2 nanoplate, and MXene-TiO2 nanoparticle structures, respectively. The explicit selectivity and high sensitivity of MXene nanoribbons toward NO2 gas are expected to provide exciting opportunities for personal safety and environmental monitoring.

Vacancy and Growth Modulation of Cobalt Hexacyanoferrate by Porous MXene for Zinc Ion Batteries

AbstractPrussian blue analogs (PBAs) featuring with 3D open framework are recognized as promising cathode candidates for Zinc‐ion batteries (ZIBs). However, challenges such as unsatisfactory active site utilization, low conductivity, and abundant structural vacancies have impeded fulfillment of their potential. In this work, a conductive in‐plane porous MXene is for the first time adopted as a multifunctional host material to enhance cobalt hexacyanoferrate (CoHCF) growth and crystallinity. Particularly, the uniform surface charges on MXene are identified to induce anisotropic and highly crystalline CoHCF, which are critical to alleviating the practical drawbacks associated with the PBAs family. Empowered by the targeted modification, the CoHCF nanotube/MXene composite realizes high surface area and low defectiveness, resulting in an impressive capacity of 197 mAh g−1 at 0.1 A g−1 and capacity retention of 95.3% over 3000 cycles at 2.0 A g−1. X‐ray spectroscopy and density functional theory (DFT) reveal that Co─C bonds in the heterostructure facilitate rapid electron/Zn‐ion transfer, enhancing Zn storage kinetics. To validate practical applicability, pouch cells incorporating Zn|CoHCF/MXene are further examined. This composition strategy, utilizing MXene as a multifunctional template, enhances the surface area, conductivity, and crystallinity of PBAs as cathodes for ZIBs, showcasing the significant potential for large‐scale energy storage applications.

Highly matched porous MXene anodes and graphene cathodes for high-performance aqueous asymmetric supercapacitors

Aqueous asymmetric supercapacitors (ASCs) provide promising prospects for electronic systems in the future that require high energy density, power density and cycling life, due to their advantages such as low cost, safe operation and environmental friendliness. However, developing well-matched anodes and cathodes with complementary potential windows and coordinated charge storage kinetics remains a significant challenge. Here, we constructed porous MXene- and graphene-based films with nitrogenous and phosphorous terminals as anodes and cathodes, respectively, alleviating the restacking of nanosheets, generating more electrochemical active sites and improving the electrolyte penetration. The assembled aqueous ASCs based on the porous MXene and graphene films could achieve an excellent energy density of 26.8 Wh kg−1 at 425 W kg−1, high rate performance, and remarkable cycling stability with 97.3 % retention after 20,000 cycles. This work demonstrates a novel concept to develop high-performance aqueous ASCs by surface engineering of two-dimensional porous electrodes with matched structural and electrochemical properties.

High-performance electromagnetic wave absorption by two-dimensional mesoporous monolayer Ti3C2Tx MXene

Transition metal carbide MXene, with its unique chemical composition, structure and sizeable particular surface area, is widely applied in wave absorption. However, the high conductivity of MXene resulted in an impedance mismatch that prevented electromagnetic waves from entering the material to achieve dissipation, and thus, tuning the intrinsic properties of pure MXene to obtain excellent electromagnetic wave absorption is still a challenge. Here, we strengthen the absorption of electromagnetic waves by generating titanium vacancies through hydrogen peroxide etching and thus forming micro-sized wrinkles with porous MXene. Porous MXene possesses an excellent microstructure and surface state, abundant porous defects, and moderate electrical conductivity, allowing it to achieve well-matched impedance, dipole polarization, and conduction loss, thus inheriting excellent electromagnetic wave absorption (EWA) properties. Therefore, the porous MXene achieves a strong absorption of − 63.31 dB and an adequate absorption bandwidth (EAB) of 6.88 GHz at a matched thickness of 2.39 mm with a fill ratio of 6 wt%.

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

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

Enhanced uranium adsorption performance of porous MXene nanosheets

The recovery of uranium from nuclear wastewater holds considerable importance in safeguarding water resources and addressing the issue of nuclear energy scarcity. Recently, modified MXenes have emerged as a promising adsorbent for U(VI)-containing wastewater due to their abundant active sites and exceptional radiation resistance, but the incorporation of costly functional molecules is usually necessary to yield satisfactory performance. In this work, we synthesized a novel kind of nano-porous Ti3C2Tx MXene nanosheets using a simple pore-creating method with Cu2+ as catalysts, which were tested for U(VI) elimination. Impressively, the U(VI) adsorption capacity (299 mg/g) of the porous MXene nanosheets surpassed that of most previously reported modified MXene and other materials. Meanwhile, Pseudo-second-order kinetics and Freundlich models provided suitable descriptions of the adsorption process, indicating heterogeneous chemisorption occurred. Experimental and spectral analysis suggested that the enhanced U(VI) adsorption capacity of the porous MXene nanosheets primarily benefited from more active OH groups on their surface to form bidentate coordination with U(VI). This work provided a valuable concept for preparing new MXene-based adsorbent for uranium removal.

Sonochemically synthesized porous V2CTx MXene/red-black phosphorus composite: A promising electrode for supercapacitors

Densely packed structure of MXene leads to less utilization of active material and thus show the mediocre performance. Fabrication of electrolyte-accessible, porous MXene composites with high rate capability and improved cycle life still needs to be looked upon. Herein, we've synthesized a red/black phosphorus (RBP) hybrid via an efficient and sustainable sonochemical route using low-cost red phosphorus (RP) in different solvents. RBP hybrid was then incorporated between V2CTx MXene layers to fabricate hetero-structured 3D V2CTx MXene-red/black phosphorus nanohybrid (MXRBP) as an electroactive material for supercapacitors. Red/black phosphorus prevented the MXene sheet from restacking and the resulted highly porous structure offered large electrochemically active surface area (ECSA ∼2125 m2 g−1). The MXRBP nanocomposite electrode blends the superior electrochemical characteristics of V2CTx MXene and the mechanical resilience of RBP. Therefore, the synergy in MXRBP||MXRBP symmetric cell result in energy density of 55 Wh Kg−1 @452 W Kg−1. This study, which is based on the design and fabrication of MXene based materials, is anticipated to offer a broad foundation for the next generation energy storage devices.

Self-standing porous MXene film via in situ formed microgel induced by 2- methylimidazole for high rate supercapacitor

Ti3C2Tx MXene has been considered a potential supercapacitor electrode material on account of its fast electron transfer performance, large volume pseudocapacitance, excellent hydrophilicity and mechanical properties. However, the serious stacking of MXene nanosheets reduced the exposed active sites and hindered diffusion of ions, leading to bad electrochemical property. Here, we report a strategy to transform MXene nanosheets into 3D MXene microgels induced by 2-methylimidazole. Benefitting from the existence of microgels, it facilitates the rapid vacuum filtration to prepare the porous MXene film, thus enhancing the ion transfer efficiency. Furthermore, 2-methylimidazole can also act as an intercalated agent to increase the layer spacing of MXene nanosheets. Therefore, the as-prepared porous MXene film demonstrates a superior rate capacity, and its capacitance reaches 223.4 F g−1 at the scan rates of 1000 mV s−1. Moreover, the assembled MXene//AC asymmetrical supercapacitor displays a 16.88 Wh kg−1 at a power density of 799 W kg−1, and maintains 13.11 Wh kg−1 at a power density of 8 kW kg−1. This work develops a simple way to prepare the porous MXene film for supercapacitors with excellent electrochemical performance.

Subtractive Nanopore Engineered MXene Photonic Nanomedicine with Enhanced Capability of Photothermia and Drug Delivery for Synergistic Treatment of Osteosarcoma.

Two-dimensional (2D) nanomaterials as drug carriers and photosensitizers have emerged as a promising antitumor strategy. However, our understanding of 2D antitumor nanomaterials is limited to intrinsic properties or additive modification of different materials. Subtractive structural engineering of 2D nanomaterials for better antitumor efficacy is largely overlooked. Here, subtractively engineered 2D MXenes with uniformly distributed nanopores are synthesized. The nanoporous defects endowed MXene with enhanced surface plasmon resonance effect for better optical absorbance performance and strong exciton-phonon coupling for higher photothermal conversion efficiency. In addition, porous structure improves the binding ability between drug and unsaturated bonds, thus promoting drug-loading capacity and reducing uncontrolled drug release. Furthermore, the porous structure provides adhesion sites for filopodia, thereby promoting the cellular internalization of the drug. Clinically, osteosarcoma is the most common bone malignancy routinely treated with doxorubicin-based chemotherapy. There have been no significant treatment advances in the past decade. As a proof-of-concept, nanoporous MXene loaded with doxorubicin is developed for treating human osteosarcoma cells. The porous MXene platform results in a higher amount of doxorubicin-loading, faster near-infrared (NIR)-controlled doxorubicin release, higher photothermal efficacy under NIR irradiation, and increased cell adhesion and internalization. This facile method pioneers a new paradigm for enhancing 2D material functions and is attractive for tumor treatment.

Ti3C2Tx/MXene Composite Aerogel Flexible Biosensor for Measuring Occlusal Force In Situ.

Occlusal force is an important parameter for evaluating the function of the occlusal system. Traditional occlusal forces can only be measured qualitatively. Here, we report a flexible piezoresistive pressure sensor with high sensitivity and a wide measurement range for in situ occlusal force measurements through the articulating paper. The sensing layer of the flexible piezoresistive sensor is a 3D porous MXene composite aerogel, which is fabricated by vacuum freezing. The MXene piezoresistive sensor is composed of the interdigital electrodes, the sensing layer, the PI encapsulation layer, and an articulating paper encapsulation layer. The sensor shows perfect performance with high sensitivity (210.21 kPa-1), wide measurement range (∼420 kPa), and a fast response time (123 ms response time, 163 ms recovery time). The amplitude of the occlusal force, which varied with time, can be observed on the mobile phone through the wireless system with the Bluetooth module. This technique has broad application prospects in oral health. In this work, we propose a simple method and a new idea for manufacturing high-performance wearable bioelectronic sensors.

Two-Dimensional Conjugated Metal-Organic Frameworks Embedded with Iodine for High-Performance Ammonium-Ion Hybrid Supercapacitors.

Ammonium ions (NH4 + ) are emerging non-metallic charge carriers for advanced electrochemical energy storage devices, due to their low cost, elemental abundance, and environmental benignity. However, finding suitable electrode materials to achieve rapid diffusion kinetics for NH4 + storage remains a great challenge. Herein, we report a two-dimensional conjugated metal-organic framework (2D c-MOF) for immobilizing iodine as a high-performance cathode material for NH4 + hybrid supercapacitors. Cu-HHB (HHB = hexahydroxybenzene) MOF embedded with iodine (Cu-HHB/I2 ) features excellent electrical conductivity, highly porous structure, and rich accessible active sites of copper-bis(dihydroxy) (Cu-O4 ) and iodide species, resulting in a remarkable areal capacitance of 111.7 mF cm-2 at 0.4mA cm-2 . Experimental results and theoretical calculations indicate that Cu-O4 species in Cu-HHB play a critical role in binding polyiodide and suppressing its dissolution, as well as contributing to a large pseudocapacitance with adsorbed iodide. In combination with porous MXene anode, the full NH4 + hybrid supercapacitors deliver an excellent energy density of 31.5 mWh cm-2 and long-term cycling stability with 89.5% capacitance retention after 10,000 cycles, superior to those of the state-of-the-art NH4 + hybrid supercapacitors. This study sheds light on the material design for NH4 + storage, enabling the development of novel high-performance energy storage devices. This article is protected by copyright. All rights reserved.

Simultaneous improvement of wetting resistance and permeability in membrane distillation using MXene-foam coating layer with heterostructural channels

To alleviate global water scarcity, membrane distillation (MD) has been identified as a promising technology for desalination. However, there exists a trade-off effect between membrane permeability and anti-wetting performance, impeding the intensive application of MD. To address this problem, inspired by the ion-sieving effect and the special nanostructure of aquaporins to break the trade-off between permeability and selectivity, a porous MXene coating layer with heterostructural channels in fusiform shape was designed on a PVDF membrane through a hydrazine-induced approach. The coating layer was in a foam shape with hydrophobic surfaces and outstanding stability in water. The delicate-designed fusiform channels endowed the membrane with enhanced permeability (the average flux of the optimum modified membrane was 55.59 kg/m2h with a temperature gradient of 60 °C (feed temperature: 70 °C and permeate temperature: 10 °C) and flow velocity of 400 ml/min, nearly 2.5 times as high as that of the virgin membrane) and resistance to simultaneous sault induced and foulant-induced wetting performance. This paper proposed a novel strategy for engineering porous nanostructures with dual-spacing channels on the membrane surface to ensure high permeability and stable excellent desalination performance.

Functional Tailoring of Multi-Dimensional Pure MXene Nanostructures for Significantly Accelerated Electromagnetic Wave Absorption.

Transition metal carbide (Ti3 C2 Tx MXene), with a large specific surface area and abundant surface functional groups, is a promising candidate in the family of electromagnetic wave (EMW) absorption. However, the high conductivity of MXene limits its EMW absorption ability, so it remains a challenge to obtain outstanding EMW attenuation ability in pure MXene. Herein, by integrating HF etching, KOH shearing, and high-temperature molten salt strategies, layered MXene (L-MXene), network-like MXene nanoribbons (N-MXene NRs), porous MXene monolayer (P-MXene ML), and porous MXene layer (P-MXene L) are rationally constructed with favorable microstructures and surface states for EMW absorption. HF, KOH, and KCl/LiCl are used to functionalize MXene to tune its microstructure and surface state (F- , OH- , and Cl- terminals), thereby improving the EMW absorption capacity of MXene-based nanostructures. Impressively, with the unique structure, proper electrical conductivity, large specific surface area, and abundant porous defects, MXene-based nanostructures achieve good impedance matching, dipole polarization, and conduction loss, thus inheriting excellent EMW absorption performance. Consequently, L-MXene, N-MXene NRs, P-MXene ML, and P-MXene L enable a reflection loss (RL ) value of -43.14, -63.01, -60.45, and -56.50dB with a matching thickness of 0.95, 1.51, 3.83, and 4.65mm, respectively.