MXene Sheets Research Articles

Preparation of interconnected tin oxide nanoparticles on multi-layered MXene for lithium storage anodes

MXenes, a novel class of two-dimensional (2D) materials known for their excellent electronic conductivity and hydrophilicity, have emerged as promising candidates for lithium-ion battery anodes. This study presents a simple wet-chemical method for depositing interconnected SnO2 nanoparticles (NPs) onto MXene sheets. The SnO2 NPs act as both a high-capacity energy source and a spacer to prevent MXene sheets from restacking. The highly conductive MXene facilitates rapid electron and lithium-ion transport and mitigates the volume changes of SnO₂ during the lithiation/delithiation process by confining the SnO₂ NPs between the MXene layers. This composite anode, SnO2@MXene, leverages the high capacity of SnO2 and the structural and mechanical stability MXene provides. The SnO2@MXene anode exhibits superior electrochemical performance, with a high specific capacity of 678 mAh g− 1 at a current rate of 2.0 A g− 1 over 500 cycles, outperforming pristine MXenes and SnO2 nanoparticles.

Ti3C2Tx MXene‐Polyaniline Nanocomposite as an Adsorbent in Microextraction by Packed Sorbent for the Analysis of Parabens in Water and Juice Samples

ABSTRACTHerein, a novel Ti3C2Tx MXene and polyaniline nanocomposite is successfully synthesized and used for the highly efficient extraction of parabens. Polyaniline (PANI) nanofibers have formed a porous and peculiar π–π conjugated structure on hydrophilic MXene sheets, providing numerous adsorption sites for microextraction of analytes with moderate polarities such as parabens. The method is simple and sensitive, using microextraction by packed sorbent coupled with a high‐performance liquid chromatography‐ultraviolet detector. Under the optimal conditions, the method provides suitable preconcentrating factors of 28–35, ultrahigh sensitivity with low limits of detection of 0.3–0.5 µg/L, wide linearity of 0.3.0–200 µg/L with coefficients of determination ≥ 0.9983, and satisfactory precision with relative standard deviations ≤ 10.7%. The outstanding performance has been confirmed in well water and orange juice samples, with recoveries in the range of 93.1%–101.2% for water and 90.6%–103.4% for orange juice samples, respectively.

Proton-Driven Dynamic Behavior of Nanoconfined Water in Hydrophilic MXene Sheets.

Liquid water under nanoscale confinement has attracted intensive attention due to its pivotal role in understanding various phenomena across many scientific fields. MXenes serve an ideal paradigm for investigating the dynamic behaviors of nanoconfined water in a hydrophilic environment. Combining deep neural networks and an active learning scheme, here we elucidate the proton-driven dynamics of water molecules confined between V2CTx sheets using molecular dynamics simulation. Firstly, we have found that the Eigen and Zundel cations can inhibit water-induced oxidation by adjusting the orientation of water molecules, thus proposing a general antioxidant strategy. Besides, we also identified a hexagonal ice phase with abnormal bonding rules at room temperature, rather than only at ultralow temperatures as other studies reported, and further captured the proton-induced water phase transition. This highlighted the importance of protons in the maintaining stable crystal phase and phase transition of water. Furthermore, we discussed the conversions of different water structures and water diffusivity with changing proton concentrations in detail. The results provide useful guidance in practical applications of MXenes including developing antioxidant strategies, identifying novel 2D water phases and optimizing energy storage and conversion.

Structural design and investigation of Ti3C2 MXene as a conductive interlayer for improving the lithium-storage performance of PSi@C anode material

Silicon stands out as an ideal anode material for the next generation of lithium-ion batteries (LIBs) due to its abundant sources, low lithiation/delithiation potential, and high specific capacity. However, its practical application is impeded by significant volume expansion, leading to electrode structure damage. In this study, the Porous silicon(PSi)@C/Ti3C2 MXene composite was developed by dispersing porous micro-silicon@carbon (PSi@C) particles into layered stackable Ti3C2 MXene sheets using ultrasonic and freeze drying. The Ti3C2 MXene interlayer played a crucial role in enhancing the conductive crosslinking network between PSi@C particles, and providing efficient channels for electron transport/ion diffusion. Additionally, the Ti3C2 MXene interlayer served as a buffer to accommodate the substantial volume changes in silicon during electrochemical cycling. Consequently, the PSi@C/Ti3C2 MXene composite electrode demonstrated rapid electron/ion conduction and maintained structural stability. Remarkably, the electrode exhibited outstanding long cycle stability with 952 mAh g-1 at 0.5 A g-1 after 200 cycles and excellent rate performance with 542 mAh g-1 at 2 A g-1.

3D Ternary Hybrid of VSe2/e‐MXene/CNT with Promising Energy Storage Performance for High Performance Asymmetric Supercapacitor

MXene and TMDs are two of the emerging electrode materials for supercapacitors owing to their unique physicochemical properties such as high conductivity, large surface area, and rich redox active sites. However, sheet restacking, volume expansion and oxidation hinder these materials from being used in practical applications. In this work, a 3D ternary hybrid structure of metallic VSe2, Ti3C2Tx MXene and carbon nanotube was designed to address some of the challenges in 2D materials‐based electrodes for supercapacitor application. The exfoliated MXene and CNT decorated VSe2 3D structure showed excellent synergy between each component to deliver promising energy storage and cycling performance. The ternary hybrid structure also can suppress the surface oxidation of MXene sheets during the hydrothermal reaction. Furthermore, an asymmetric supercapacitor fabricated with VSe2/e‐MXene/CNT and MoS2/MXene delivered the highest energy density of 35.91 Wh/kg at a power density of 1280 W/kg and a remarkable cycle life.

Iron-iridium metal organic framework/nitrogen doped MXene/graphene quantum dots: A leading composite for electrolytic energy storage and hydrogen evolution reaction

MXene has recently been the subject of several studies on energy storage. Outstanding qualities that are essential to energy storage applications contain its conductivity, hydrophobicity, and especially significant surface redox reactivity. But while its amazing properties, a few problems seriously restrict its electrochemical efficiency, one of them being the formation of MXene sheets. The gaps between MXene sheets need to be filled with a suitable substance to prevent them from restacking. MOFs have also been thoroughly investigated for electrochemical applications. MOFs have a wide range of uses because of their high crystallinity, porous structure, and large surface area; nevertheless, their effectiveness as electrode materials is restricted by their reduced charging/discharging rate and specific capacity. In order to overcome these drawbacks, it is suggested that MOFs be combined with appropriate materials for improved performance. This work proposes a novel strategy: a composite of graphene quantum dots (GQDs), N-MXene, and iron‑iridium MOF (Ir@Fe-MOF). The limitation of MXene sheet restacking was achieved by reducing each of the ion/electron transportation paths and boosting the electroactive sites, resulting in a remarkable specific capacity in the composite, including MOFs.In a two-electrode assembly, the Ir@Fe-MOF/N-MXene/GQDs exhibited energy and power density of around 43.3 W h kg−1 and 880 W kg−1 respectively. A Coulombic efficiency of 93.06 % and 98.48 % of capacity was maintained by the Ir@Fe-MOF/N-MXene/GQDs/activated carbon (AC) material after 5000 cycles of alternative GCD measurements. The results of this work show that supercapattery applications can gain from the new electrode material Ir@Fe-MOF/N-MXene/GQDs.

Rationally designed silver doped bismuth tungstate dispersed on multifunctional MXene sheets for enhanced supercapacitor applications

Rationally designed silver doped bismuth tungstate dispersed on multifunctional MXene sheets for enhanced supercapacitor applications

Electrostatically self-assembled magnetized MXene/copper ferrite nanospheres hybrids: Evaluation of molecularly imprinted electrochemical sensor for the quercetin antioxidant supplement

Quercetin, a bioflavonoid with significant biological activities, is beneficial for health. Herein, a pioneering molecularly imprinted electrochemical sensor utilizing an MXene/CuFe2O4 magnetic nanosphere hybrid was developed for the first time to detect quercetin ultra-sensitively. CuFe2O4 nanospheres (average 189 nm) were synthesized and combined with MXene sheets, then electrostatically deposited onto a magnetic carbon paste electrode. A functional monomer was then electropolymerized onto this hybrid-modified electrode to form an imprinted polymeric layer, tailored for quercetin binding. Characterizations confirmed the morphological and magnetic properties of the materials. The sensor’s response factors were optimized, achieving a low detection limit of 1.6 nM and two linear ranges (0.005–0.7 μM and 0.7–10 μM). The sensor showed excellent stability, repeatability, reproducibility, and selectivity, and was successfully used to quantify quercetin in dietary supplements.

Ag-doped MgCo2O4/MXene composite: Tailoring the electrochemical properties via 2D layered material for next generation supercapacitor study

The major concern of the modern era is to conserve and store energy for future use because of the continuous depletion of natural resources. Spinel cobaltites have attracted a lot of attention to be studied in the energy storage and conversion arena because of their prospective applications and excellent electrochemical performance. Achieving excellent chemo-mechanically robust electrode materials requires creative structural design and effective multicomponent strategy implementation. Herein, MgCo2O4 (MC) and Ag-MgCo2O4 (AMC) were fabricated by hydrothermal treatment. Further, Ag-MgCo2O4 (AMC) coupling with MXene sheets was accomplished by ultrasonication treatment. After structural, morphological, functional, and compositional analyses, prepared materials were studied for supercapacitor measurements. AMC/MXene exhibited remarkable outcomes because of Ag ions insertion into the spinel oxide structure, providing electron transport paths by creating voids and interfacial contact between the electrolyte and available active sites, and 2D MXene layers boosting the transportation of ions during the charging and discharging stages. The specific capacitance at 1 Ag−1 was found to be 1722 Fg−1 for AMC/MXene. The bulk (solution) resistance Rs was found to be the lowest 0.63 Ω for AMC/MXene among other fabricated materials in this study. Hence, developing AMC/MXene offers an advanced method to build high-performance 2D electrode materials with hybrid structures for energy storage applications.

Enhanced dopamine detection using Ti3C2Tx/rGO/Pt ternary composite synthesized via microwave-assisted hydrothermal method

A novel electrochemical sensing platform for dopamine (DA) detection was developed by fabricating the ternary composite of Ti3C2Tx MXene (M) and reduced graphene oxide (rGO) with platinum nanoparticles (Pt NPs) through microwave-assisted hydrothermal heating. The exceptional electrical conductivity and rich surface chemistry of MXene provide abundant active catalytic sites for electrochemical reactions, while the large surface area of rGO facilitates ion and electron pathways. The integration of rGO in the MXene sheet, forming MXene-rGO (M_rGO) heterostructure composite, imparts long-term stability to the 2D heterostructure while providing additional electron pathways and significantly enhancing conductivity. Pt NPs synergistically increased the electrocatalytic activity of the electrochemical sensor's performance. Ternary nanocomposites were fabricated with different weight percentages (wt.%) of Pt NPs, ranging from 5 to 20. Characterizations of the samples (rGO, M, M_rGO, and 5–20 wt% Pt@M_rGO) were conducted through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy (RAMAN), and X-ray spectroscopy (XPS). Electrochemical evaluations of the samples were investigated in 0.1 M phosphate buffer solution (PBS) using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) analyses. The analysis revealed that the ternary composite with 5 wt% of Pt NPs (5% Pt@M_rGO) exhibited a uniform well-distribution of Pt NPs and the highest oxidation peak for DA oxidation in CV studies. The presence of metal nanoparticles, aided by the synergistic effects between the MXene and rGO, resulted in an excellent DA sensor with a 0.147 μM detection limit from 1 to 14 μM linearity range. The sensor demonstrated outstanding selectivity, reproducibility (RSD values of 8.10%), repeatability (RSD value of 2.46%) and, excellent stability over 14 days. In human urine samples, the sensor exhibited excellent DA recovery (88.62–110.65%). This study significantly advances the development of electrochemical sensors for DA detection by introducing a rapid, facile and, efficient method for fabricating ternary composites. The fabricated sensor exhibited high sensitivity, excellent selectivity, and robust electrochemical performance, offering valuable insights into human and behavioral health advancements.

Optimum ultrasonication duration for effective antimicrobial activity of Ti3C2-MXene

The characteristics of two-dimensional (2D) nanomaterials have attracted remarkable attention, particularly in the fields of environmental engineering, sciences and medicine. This study was focused on Ti3C2Tx-MXene, a novel 2D nanomaterial known for its antibacterial efficacy against both Gram-negative and Gram-positive bacteria. Our investigation has represented the initial exploration of the primary antifungal capabilities of Ti3C2Tx-MXene nanosheets, with variations in lateral size induced by ultrasonication time. The Ti3C2-MXene, characterized by negative surface potential, was tested against Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Enterobacter cloacae and fungal strains of Candida albicans. Ultrasonication was employed without the use of any chemical intercalant for delamination, separation, and exfoliation. The optimal ultrasonication duration was determined, revealing the minimum inhibitory concentrations of 8 μl/mL and 4 μl/mL against E. coli and S. aureus, respectively, as observed through the broth dilution test. The antifungal activity against Candida albicans has been assessed using the well diffusion method, revealing a substantial zone of inhibition measuring 14 mm. The demonstrated antimicrobial efficacy of ultrasonicated MXene sheets has shown a huge potential for serving as an effective anti-biofouling material.

Facile synthesis of MXene from MAX phase via Hydrothermal method using a mild etchant

The present study explains an effective and efficient synthesis of MXene (Ti3C2TX) from MAX phase (Ti3AlC2) via hydrothermal method in presence of a mild etchant that is an affordable, safe, easy to handle and environmentally friendly approach. The successful synthesis of MXene from MAX phase was explained on the basis of shifting of (002) plane towards lower angle with significantly enhancement in the corresponding FWHM of the peak, which demonstrates the enhanced interlayer spacing of MXene sheets. The lower intensity of peak corresponding to (104) plane shows removal of aluminum layer from MAX phase with a very small quantity of aluminum content as analyzed from X-ray diffractogram and EDS spectrum. The enhanced interlayer spacing are also clearly visible in FESEM images and comes out to be an average of ∼42 nm. The elemental distribution mapping shows the purity of MXene with fluorine as a functional group because of using mild fluoride etchant. The optical and electrochemical properties also support the synthesis of efficient and high purity MXene. The synthesized MXene can be proven as a promising material for a wide variety of applications from environmental remediation to electrochemical sensing and energy storage, leading to their increasing popularity in the research and scientific field.

Proton‐Driven Dynamic Behavior of Nanoconfined Water in Hydrophilic MXene Sheets

Liquid water under nanoscale confinement has attracted intensive attention due to its pivotal role in understanding various phenomena across many scientific fields. MXenes serve an ideal paradigm for investigating the dynamic behaviors of nanoconfined water in a hydrophilic environment. Combining deep neural networks and an active learning scheme, here we elucidate the proton‐driven dynamics of water molecules confined between V2CTx sheets using molecular dynamics simulation. Firstly, we have found that the Eigen and Zundel cations can inhibit water‐induced oxidation by adjusting the orientation of water molecules, thus proposing a general antioxidant strategy. Besides, we also identified a hexagonal ice phase with abnormal bonding rules at room temperature, rather than only at ultralow temperatures as other studies reported, and further captured the proton‐induced water phase transition. This highlighted the importance of protons in the maintaining stable crystal phase and phase transition of water. Furthermore, we discussed the conversions of different water structures and water diffusivity with changing proton concentrations in detail. The results provide useful guidance in practical applications of MXenes including developing antioxidant strategies, identifying novel 2D water phases and optimizing energy storage and conversion.

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.

Tailoring surface terminals of Ti3C2Tx MXene microgels via interlayer domain-confined polyphosphate ammonium for flexible supercapacitor applications

The MXene material shows potential for flexible energy storage devices due to its high pseudocapacitance and mechanical flexibility. However, MXene nanosheet self-stacking and –F terminal functional groups can hinder active site and ion dynamics, thus affecting the energy storage performance. Herein, we present an interlayer domain-confined strategy that involves the introduction and crosslinking of ammonium polyphosphate (APP) confined to the interlayer of Ti3C2Tx MXene sheets, which induces gelation of the MXene to form a 3D network structure and enlarge their interlayer spacing. And then the cross-linked APP is converted into nitrogen and phosphorus terminals on Ti3C2Tx MXene via thermal treatment. The nitrogen terminals in the form of the pyrrole nitrogen and pyridine nitrogen, and phosphorus terminals of P–O bonds enhance the activity of the redox reaction and the dynamics of the ions, resulting in the boosted energy storage capacity of MXene. The density functional theory (DFT) calculations reveal that nitrogen-phosphorus co-doping modulates the surface electronic states of MXene and contributes to the increase of the electrical conductivity of Ti3C2Tx MXene. As a supercapacitor electrode, Ti3C2Tx MXene with N/P terminals exhibits a higher specific capacitance of 597.8 F/g (1777F cm−3) than the raw Ti3C2Tx MXene (384 F/g). In addition, the quasi-solid state flexible symmetric supercapacitor assembled by Ti3C2Tx MXene with N/P terminals can achieve an energy density of 12.5 Wh kg−1 at a power density of 250 W kg−1. Therefore, this work provides a new strategy for terminal modification of MXene and high-performance MXene supercapacitors.

Scalable synthesis of 2D-layered Ti3C2 MXene by HF etching method; electrochemical investigations and device fabrication to enhancing capacitive nature

The goal of the current effort is aimed to synthesise the uniform exfoliated titanium carbide (Ti3C2) MXene sheets by utilising hydrofluoric (HF) acid to remove/etch “aluminium” from the parental Ti3AlC2 MAX phase. The Ti3C2 MXene was investigated by structural analysis using X-ray diffraction (XRD), Higher Resolution Transmission Electron Microscope (HRTEM), Scanning electron microscope (SEM), and EDS with mapping for morphological and elemental analysis, Moreover, the Ti3C2 MXene was studied its electrochemical properties to electrochemical energy storage application using cyclic voltammetry (CV), Galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) techniques. Since the GCD analysis of Ti3C2 MXene, a great specific capacitance (Csp) of 318F/g was attained with current density of 1 A/g and up to 90 % retentivity was attained after 7500 cycles. Besides, fabricated Ti3C2 MXene||Ti3C2-MXene symmetric supercapacitor device (SSD) has described the energy density (ED) of 27.78 Wh/kg at a power density (PD) of 400 W/kg and the capacitive retention existed attained 92.1 % after 7500 cycles with 5 A/g.

All-solid-state flexible micro-supercapacitors with enhanced electrochemical performance obtained by hybridizing mxene with butterfly graphite

Abstract All-solid-state flexible micro-supercapacitors (MSCs) have the advantages of large energy storage capacity, small size, and good flexibility, which can be used as micro power sources. A 2D titanium carbide (MXene) has metallic conductivity, good hydrophility, and excellent processing properties, showing its great potential in flexible MSCs. However, the self-packing of MXene sheets hinders charge transfer and ion transport, limiting its electrochemical capacity. Herein, MSCs were prepared from a composite material of butterfly-like graphite (BTG) and MXene. BTG was inserted into the MXene layer to prevent its overs tacking, which promotes the diffusion of electrolytes and improves the electrochemical capacity of MSCs. As a result, MXene/BTG MSCs exhibit a large capacitance of 177.9 mF cm−2 at 5 mV s−1. In addition, the specific capacitance retention of MXene/BTG-30% MSCs can reach 80.4% in 0.1 -1 mA cm−2.

In-situ grown ternary metal hydroxides@3D oriented crumpled V2C MXene sheets for improved electrocatalytic oxygen evolution reaction

High valence multi transition metal hydroxides are greatly enriched with OER redox active sites due to strong synergy of heteroatomic nuclei. The efficiency of these redox active sites could be efficiently improved by coupling with highly conductive substrate. The advanced three-dimensional (3D) architecture and hydrophilic terminal functionalities of MXene (MX) considerably enhance the maximum utilization rate of anchored redox active sites by triggering the direct growth of these at MX substrate. Here-in, the freeze-dried 3D network of crumpled Vanadium-Carbide (V2C) MX sheets regulates the crystallization of in-situ grown NiFeCr multi transition metal hydroxides on MX scaffold through co-precipitation process. The XPS results suggest a synergistic chemical interaction of 3D MX scaffold with NiFeCr that modifies the electronic structure of the composite ensuring reduced charge transfer resistance. Besides, as found in FESEM morphological investigation, the well-dispersed NiFeCr multi-transition metal hydroxides are immobilized on open pores like structure of V2C-MX facilitate thoroughly accessible active sites. As a result, the NiFeCr@3D V2C-MX composite has shown an excellent electrocatalytic activity with an overpotential of 410 mV at a current density of 200 mA cm−2, Tafel slope of 100 mV dec in 1M KOH. Besides, the significant interaction between metallic centers and MXene support prevent detachment or agglomeration of active centers providing maximum interaction with the electrolytic ions, quick ionic OH− transportation, speedy and stable electron transfer channels thus ensure the long-term stability of NV-5MX during 53 h continuous operation of OER. Furthermore, we have utilized a more accurate value of half-cell standard reduction potential of the Hg/HgO electrode in the Nernst equation to represent all test voltages and to determine the overpotential values. In essence, this study features a facile approach for the confined growth of multi transition metal hydroxides in the presence of morphologically unique 3D crumpled V2C MXene architectures. Consequently, the increased OER reaction kinetics and improved stability of the synthesized composites are potentially due to synergistic interplay between well dispersed active sites and the conductive substrate.

Advancing nanoarchitectures of 2D WO3/MXene photoanode for enhanced photoelectrocatalytic oxidation of phenol and arsenic in synthetic wastewater

The photoelectrocatalytic advanced oxidation process (PEAOP) necessitates high-performing and stable photoanodes for the effective oxidation of complex pollutants in industrial wastewater. This study presents the construction of 2D WO3/MXene heteronanostructures for the development of efficient and stable photoanode. The WO3/MXene heterostructure features well-ordered WO3 photoactive sites anchored on micron-sized MXene sheets, providing an increased visible light active catalytic surface area and enhanced electrocatalytic activities for pollutant oxidation. Phenol, a highly toxic compound, was completely oxidized at an applied potential of 0.8 V vs. RHE under visible light irradiation. Systematic optimization of operational conditions for the photoelectrocatalytic oxidation of phenol was conducted. The phenol oxidation mechanism was elucidated via high-performance liquid chromatography (HPLC) analysis and the identification of intermediate compounds. Additionally, a mixed model of phenol and arsenic (III) in polluted water demonstrated the capability of WO3/MXene photoanode for the simultaneous oxidation of both organic and inorganic pollutants, achieving complete conversion of phenol and As(III) to non-toxic As(V). The WO3/MXene photoanode facilitated water oxidation, generating a substantial amount of O2•– and •OH oxidative species, which are crucial for the concurrent oxidation of phenol and arsenic. Recyclability tests demonstrated a 99% retention of performance, confirming the WO3/MXene photoanode's suitability for long-term operation in PEAOPs. The findings suggest that integrating WO3/MXene photoanodes into water purification systems can enhance economic feasibility, reduce energy consumption, and improve efficiency. This PEAOP offers a viable solution to the critical issue of heavy metal and organic chemical pollution in various water bodies, given its scalability and ability to preserve ecosystems while conserving clean water resources.

Tailoring surface terminals on MXene enables high-efficiency electromagnetic absorption

MXene (Ti3C2Tx) is an important category of two-dimensional (2D) materials due to its distinctive metallic conductivity and adjustable surface chemistry. The exceptional benefits of heterointerface and defects or viods, combined with the distinct electromagnetic (EM) properties, inject boundless potential into the advancement of MXene-based absorbers for EM absorbing materials. However, conventional synthetic methods depend on chemical etching of MAX powders (Ti3AlC2) using hazardous HF or similar substances, resulting in MXene sheets with fluorine termination and limited stability in colloidal dispersions under ambient conditions. Herein, varied synthetic routes were proposed to prepare MXenes with different terminal groups by the fluoride-based salts, fluoride-free molten salts, and alkali etching. 2D MXene nanosheets with abundant surface groups are excellent EM absorbing materials, and the MXene etched by the Lewis acid CuCl2 delivered remarkable reflection loss (RL) value of −47.56 dB at 2.5 mm and broad bandwidth of 4.8 GHz due to promoted interfacial polarization. By conducting a thorough examination of the structural changes in MXenes, this study aims to propose a viable method for delaminating single-layer MXene and elucidate the EM absorption mechanisms.