Ti3C2 MXene Research Articles

Peroxidase-like manganese oxide nanoflowers-delaminated Ti3C2 MXene for ultrasensitive dual-mode and real-time detection of H2O2 released from cancer cells

Hydrogen peroxide (H2O2), a crucial biomarker of reactive oxygen species (ROS), is pivotal in diagnosing and treating cancer. Due to H2O2’s low concentration, fast diffusion, and natural degradation, traditional sensing single-readout methods have issues reliably monitoring and quantifying the cancer cells. Herein, to improve accuracy and an efficient way to boost the signals and increase the sensitivity, a dual-mode electrochemical (EC) and electrochemiluminescence (ECL) sensing system for monitoring H2O2 release from cancer cells in real-time has been developed using in-situ self-assembly of polycrystalline manganese oxide nanoflowers (cubic Mn2O3 and orthorhombic Mn3O4, MnxOy NFs) on the Ti3C2 MXene nanosheets. Peroxidase mimics of MnxOy/Ti3C2 MXenes serve not only as a co-reaction accelerator but also as a substrate for immobilizing high loading of luminol (LUM), which accelerates the generation of ROS and decreased the distance between the LUM and the generated OH. The hollow layered structure of Ti3C2 MXene as well as the synergistic effect of strong interaction between MnxOy NFs and Ti3C2 MXenes enhanced the heterostructures’ exceptional catalytic performance. The sensor demonstrated a unique 1.5 s current response for H2O2 detection, with an electrochemistry-wide linear response ranging from 0.05 to 650 μM and an ultrasensitive ECL limit of detection of 0.45 nM. The biosensor is remarkably effective in measuring the H2O2 released from breast cancer (MCF-7) under ascorbic acid simulation with a dynamic range of 100–6000 cell numbers, a low detection limit (20 cells), desirable anti-interference characteristics, and substantial capability to distinguish cancer cells from normal cells.

Mussel-inspired polydopamine (PDA)-grafted 2D-Ti3C2 MXene nanosheets tailored ZnAl-layered double hydroxides (LDH); Toward designing a smart self-healing epoxy composite coating

The constant challenge of corrosion significantly compromises the durability and functionality of metal substrates, propelling the demand for advanced protective solutions. This study introduces a novel smart epoxy coating system modified with a three-component nanocomposite integrating polydopamine (PDA)-modified Ti3C2 MXene with ZnAl-layered double hydroxides (LDH), intercalated with phosphate (P) and glutamate (Gl) ions as corrosion inhibitors. The innovative approach leverages the synergistic impacts of barrier protection, ion exchangeability, and self-healing capabilities to offer superior anti-corrosion performance. In the solution phase, the EIS results revealed a notable increase in resistance values, with MPLG samples exhibiting a 2.45-fold and MPLP samples a 2.17-fold enhancement compared to the blank specimen after 96 h of immersion. Furthermore, the data obtained from EIS demonstrated a significant enhancement in the barrier effects of the epoxy coating upon the addition of MPLG and MPLP. This enhancement was evidenced by a significant increase in the impedance values, which were observed to be 103-fold higher following a prolonged immersion period of 140 days. The self-healing properties, confirmed through EIS, FE-SEM, and EDX/Mapping analyses, indicated the formation of a stable corrosion-protective layer over the damaged areas, thus providing active protection. Adhesion assessments further underscored the coatings' durability, with MPLG and MPLP samples demonstrating minimal delamination. Collectively, these findings emphasize the potential of the proposed PDA-modified MXene@ZnAl-LDH nanocomposite as a multifaceted solution to corrosion challenges, promising significant advancements in the longevity and reliability of coated metal surfaces.

Photo-induced time-dependent controllable wettability of dual-responsive multi-functional electrospun MXene/polymer fibers

Switchable wettability potential in smart fibers is of paramount importance in various applications. Light-induced controllable changes in surface wettability have a significant role in this area. Herein, smart waterborne homopolymer, functional copolymer with different polarity and flexibility, and multi-functional terpolymer particles containing a time-dependent dual-responsive acrylated spiropyran, as a polymerizable monomer, were successfully synthesized through eco-friendly single-step emulsifier-free emulsion polymerization. Presence of 10 wt% of butyl acrylate and dimethylaminoethyl methacrylate relative to methylmethacrylate as functional comonomers decreased the Tg of the samples almost 20 ℃ and increased their polarity. The optical properties of the particles were investigated, and the UV–vis and fluorescence spectroscopy results showed that not only polarity and flexibility of the polymer chains may have a positive effect on improving the optical properties, but also the simultaneous presence of functional groups has a synergistic effect. The smart polymer particles with flexibility and polarity features exhibited higher absorption and emission compared to other samples. Inspired by these findings, multi-functional smart polymer fibers were prepared using the electrospinning method. The smart multi-functional electrospun fibers containing few-layer Ti3C2 MXenes were synthesized to improve the fibers’ properties and change the surface wettability due to the hydrophilic functional groups of MXene. Field-emission scanning electron microscopy images displayed the successful preparation of few-layer MXenes. Smooth and bead-free fibers with bright red fluorescence emission under UV irradiation were shown using fluorescence microscopy. The study on the surface wettability of fibers revealed that UV and visible light irradiation induced reversible time-dependent changes in the wettability of the smart multi-functional MXene/polymer electrospun fibers from hydrophobic to hydrophilic, reaching a water contact angle of 10° from an initial water contact angle of 100° under UV light and also changing to superhydrophilic state with passing time. Upon visible light exposure, the fibers returned to their original state. Furthermore, the fibers demonstrated a high stability over five alternating cycles of UV and visible light irradiation. This study shows that the fabrication of time-dependent smart fibers, utilizing the flexibility and polarity in the presence of MXenes, significantly improves and controls surface wettability changes. The outstanding dynamically photo-switchable wettability of these fibers may offer exciting opportunities in various applications, especially in the separation of oil from water contaminants.

Research on the Performance of New Microbial Fuel Cell Anodes

In recent years, with the vigorous development of the maritime transportation industry, the resulting problem of ship oil pollution has become increasingly prominent. Efficient and thorough treatment of oily wastewater is the key to solving such problems. Microbial fuel cell (MFC) technology is a promising biological treatment method due to its good degradation effect, no secondary pollution, and energy recovery. In this paper, the discarded corn cob materials in nature were selected for high-temperature carbonization at 350°C, and NaOH was used to modify the modified biochar. Then, the coating technology of Ti3C2 MXene, NbC, WC, TaC and other materials was used to modify the surface of biochar, and the biochar anode material was obtained to construct a double-chamber microbial fuel cell device. The properties of the modified anode biochar materials were studied.

Optimizing Titanium Carbide-Silver Oxide Nanostructures for Targeted Cancer Therapy: Synthesis, Functionalization, and In Vitro Evaluations.

Introduction Cancer remains a significant health challenge, and nanoparticles (NPs) are promising candidates for cancer treatment due to their unique physicochemical properties and ability to selectively target tumour cells. Two-dimensional (2D) nanomaterials, such as MXenes, have attracted interest due to their electronic structures, optical properties, catalytic abilities, and exceptional physicochemical attributes. MXenes are highly suitable for surface functionalization or modification, and their unique properties make them promising candidates for various applications in the biological field. Silver-based compounds have shown remarkable potential in biomedical fields, with silver oxide (Ag₂O) NPs finding applications in various domains. The fabrication of titanium carbide (Ti₃C₂)-Ag₂O heterostructures has been investigated for their anti-cancer properties by conducting cell viability assays on different cell lines. Aim To synthesize and characterize Ti₃C₂-Ag₂O, and to assess its in vitro anti-cancer activity. Materials and methods Ti₃C₂ synthesis begins by dissolving Ti₃AlC₂ powder in a 50% v/v hydrofluoric (HF) acid solution, allowing the aluminium to be etched away. This process should be conducted with continuous stirring for 24 to 48 hours at ambient temperature. Following this, filter the resulting suspension to eliminate aluminium particles and HF, and subsequently wash the Ti₃C₂ MXene with distilled water until a neutral pH is attained. The MXene should then be dispersed in ethanol, and sonication in deionized (DI) water or an alternative solvent should be employed to achieve exfoliation into monolayer or few-layer MXenes. To prepare Ag₂O NPs, dissolve silver nitrate (AgNO₃) in DI water to create a 0.1 M solution, and concurrently prepare a separate 0.1 M sodium hydroxide (NaOH) solution. Introduce the NaOH solution to the AgNO₃ while stirring until a precipitate is observed. The mixture should then be filtered, washed with distilled water, and the NPs dried at 60°C for 12 hours. To fabricate the MXene-Ag₂O composite, disperse the MXene nanoflakes in a solvent through sonication, incorporate the Ag₂O NPs, and stir the mixture for 24 hours. Finally, centrifuge the resultant mixture to isolate the composite, wash it with solvent, and dry it under vacuum conditions. Results The presence of Ag₂O particles on Ti₃C₂ nanosheets was observed, and the high crystallinity of the compound was confirmed through X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM) analyses. These tests verified that the compound was free of impurities and exhibited anti-cancer properties. Conclusion The synthesis of Ti₃C₂ MXenes and Ag₂O NPs was achieved and confirmed through structural characterization methods, including SEM, XRD, and EDS. SEM provided detailed insights into the morphology and distribution of the nanostructures, while XRD and EDS verified their phase purity and elemental composition. Functionalization strategies were employed to enhance the stability and bioactivity of the nanocomposites. In vitro evaluations demonstrated promising anti-cancer activity, indicating that the Ti₃C₂-Ag₂O composites effectively target and inhibit cancer cell growth.

Nitrogen plasma-induced phase engineering and titanium carbide/carbon nanotubes dual conductive skeletons endow molybdenum disulfide with significantly improved lithium storage performance

MoS2/Ti3C2 MXene composite has emerged as a promising anode material for lithium storage due to the synergistic combination of high specific capacity offered by MoS2 and conductive skeleton provided by Ti3C2 MXene. However, its two-dimensional/two-dimensional (2D/2D) structure is susceptible to collapse after long cycles, while the inherent low conductivity of MoS2 limits its rate performance. In this study, we developed a novel approach combining plasma-induced phase engineering with dual skeleton structure design to fabricate a unique P-MoS2/Ti3C2/CNTs anode material featuring highly conductive 1T phase MoS2 and a stable one-dimensional/two-dimensional (1D/2D) architecture. Within this architecture, growth of MoS2 nanosheets on the surface of Ti3C2 cross-linked by carbon nanotubes (CNTs) was achieved. The resulting Ti3C2/CNTs dual skeleton not only provides robust mechanical support to prevent structural collapse during long cycles but also offers increased specific surface area and additional Li+ storage space, thereby enhancing the lithium storage capacity of the composite. Subsequent N2 plasma treatment induced a phase transition in MoS2 from 2H to 1T configuration. Density functional theory (DFT) calculations confirmed that the induced 1T-MoS2 exhibits higher conductivity and lower Li+ diffusion barrier compared to 2H-MoS2. Benefiting from these synergistic effects, our P-MoS2/Ti3C2/CNTs anode demonstrated remarkable electrochemical performance including a high reversible specific capacity of 1120 mAh g−1 at 0.1 A g−1, excellent cycling stability with a specific capacity retention of 670 mAh g−1 after 600 cycles at 1 A/g, and superior rate performance with a specific capacity of 614 mAh g−1 at 2 A g−1. This combined modification strategy will serve as guidance for designing other energy storage materials.

Novel sensitive electrochemical detection of paracetamol using magnetite/MXene electrode by differential pulse voltammetry

In this research work, a novel electrochemical sensor-based Fe3O4/Ti3C2 MXene @ glassy carbon electrode (GCE) for the detection of paracetamol was prepared by simple ultrasonic method by combining Ti3C2 MXene and Fe3O4 nanoparticles. The Fe3O4/Ti3C2 MXene nanomaterial was characterized by the means of different techniques: X-ray diffraction (XRD), transmission and scanning electron microscopy (TEM), nitrogen adsorption/desorption isotherms, as well as Fourier transform infrared spectroscopy (FTIR). The characterization results revealed the homogenous distribution of the prepared cubic Fe3O4 NPs within the prepared two-dimensional layered Ti3C2 MXene. The Fe3O4/Ti3C2 MXene @ GCE was used for the sensitive determination of the well-known analgesic drug paracetamol by differential pulse voltammetry (DPV). The prepared Fe3O4/Ti3C2 MXene @ GCE was characterized electrochemically, and the results showed that Fe3O4/Ti3C2 MXene @ GCE is a potential working electrode for the sensitive detection of paracetamol with very low detection limit (0.63 nM), within a linear dynamic range of 0.0–110.0 µM, high reproducibility and repeatability; with a very low relative standard deviation (SD%) for 7 days measurement (3.07–3.42 %), accuracy with a SD% of 0.89, high precision of 99.48 % in distilled water and 98.51 % in sea water. The proposed electroanalytical method was applied for the detection and quantification of paracetamol in real water samples, as well as different analgesic medical formulations, and the results showed outstanding accuracy and precision indicating the suitability of the Fe3O4/Ti3C2 MXene @ GCE electrode for the sensitive, accurate determination of paracetamol in diferrent matrices.

Enhanced adsorption of radioactive cesium from nuclear wastewater using ZIF-67 laminated 2D MXene Ti3C2

Development of nuclear industry has caused severe water pollution. Adsorptive removal of radionuclides from wastewater has been regarded as effective solution for environment. However, developing adsorbents with high adsorption capacity and selectivity for removal of radionuclides (such as 137Cs) is still a challenge. Herein, we adopted an in situ assemble strategy to construct a novel composite, in which zeolitic imidazolate framework (ZIF-67) was grafted into two-dimension (2D) layers of transition metal carbides/nitrides (MXenes) Ti3C2, and used it in adsorptive removal of Cs+ from wastewater. Laminated and pillaring effect of ZIF-67 increased interlayer spacing and specific surface area of Ti3C2, significantly enhancing Cs+ adsorption. MXenes matrix provided the main adsorptive sites and interaction to stabilize Cs+, while the hybrid ZIF-67 assisted adsorption. The adsorbent achieved 96.2 % removal for 5 mg·L-1 of Cs+ within 6 h, and 50.0 mg·g−1 of maximum adsorption capacity, with good recyclability for 4 times. Ion competition, kinetics and thermodynamics were studied in detail to obtain the behavior of Cs+ adsorption. Finally, adsorption mechanism was proposed that [Ti − O] − H+ and [Ti − O] groups of 2D Ti3C2 were main adsorptive sites to participate in ion exchange and complexation with Cs+, respectively, while 2-methylimidazole (2-MI) ligands in ZIF-67 were synergetic adsorption sites.

Organic-Inorganic Interfacial Dipole Induced by Energy Level Alignment for Efficient Photocatalytic Sterilization.

Photocatalytic molecules are considered to be one of the most promising substitutions of antibiotics against multidrug-resistant bacterial infections. However, the strong excitonic effect greatly restricts their efficiency in antibacterial performance. Inspired by the interfacial dipole effect, a Ti3C2 MXene modified photocatalytic molecule (MTTTPyB) is designed and synthesized to enhance the yield of photogenerated carriers under light irradiation. The alignment of the energy level between Ti3C2 and MTTTPyB results in the formation of an interfacial dipole, which can provide an impetus for the separation of carriers. Under the role of a dipole electric field, these photogenerated electrons can rapidly migrate to the side of Ti3C2 for improving the separation efficiency of photogenerated electrons and holes. Thus, more electrons can be utilized to produce reactive oxygen species (ROS) under light irradiation. As a result, over 97.04% killing efficiency can be reached for Staphylococcus aureus (S. aureus) when the concentration of MTTTPyB/Ti3C2 was 50 ppm under 660 nm irradiation for 15 min. A microneedle (MN) patch made from MTTTPyB/Ti3C2 was used to treat the subcutaneous bacterial infection. This design of an organic-inorganic interface provides an effective method to minimize the excitonic effect of molecules, further expanding the platform of inorganic/organic hybrid materials for efficient phototherapy.

Amino modification of Ti3C2 MXenes for high-performance supercapacitors

MXenes show great potential in energy storage due to their excellent conductivity, abundant surface groups and adjustable interlayer spacing. Amino modification is an effective strategy to improve electrochemical properties of MXene. However, the selection of amino source is still a key issue. Herein, the amino modification of Ti3C2 MXenes for high-performance supercapacitors has been investigated. The structure and electrochemical properties of Ti3C2 are modified by different amino sources, such as ethylenediamine (EDA), monoethanolamine (MEA) and hydrazine monohydrate (HM). EDA ensures Ti3C2 the largest interlayer spacing (13.96 Å) and highest specific surface area (52.2 m2g−1). In addition, there are more functional groups in EDA-modified Ti3C2 (EDA-Ti3C2) resulted from the stronger electron-donating nature of EDA than HM and MEA. Thus, EDA-Ti3C2 exhibits the largest specific capacitance of 683 F g−1 in 1 M H2SO4 electrolyte at 2 mV/s, and the capacitance maintains 97.3 % of the original after 10,000 cycles at 50 mV/s. As a comparison, MEA-Ti3C2 and HM-Ti3C2 show specific capacitances of 553 F g−1 and 470 F g−1, respectively. Furthermore, the symmetric supercapacitor based on EDA-Ti3C2 electrode achieves maximum energy density of 7.87 W h kg−1 at power density of 600 W Kg−1, and the energy density still remains at 6.34 W h Kg−1 even at an increased power density of 3000 W Kg−1. This study proposes a simple strategy to enhance electrochemical properties of MXene by amino modification, providing valuable insights for high-performance supercapacitors.

Engineering of a wafer-shaped titanium-based catalyst of TiO2/MIL-125(Ti)@Ti3C2 for enhanced Fenton-like degradation of Congo red: Optimization, mechanistic study, and reusability

A titanium-based Fenton-like heterogeneous catalyst was synthesized from titanium dioxide (TiO2), MIL-125(Ti), and Ti3C2 MXene for degrading the notorious Congo red (CR). The successful combination of the titanium components was assured by bountiful characterization apparatuses. Optimization of the conditions for the Fenton-like degradation of CR dye was performed by studying the impact of the pH and temperature of the catalytic system, the dosage of TiO2/MIL-125(Ti)@Ti3C2, the concentrations of hydrogen peroxide (H2O2) and CR, and the mass ratio between the catalyst’s components. A kinetic study was executed on the degradation of CR and H2O2 during a reaction time of 60 min using First-order and Second-order models. The degradation pathway of CR by TiO2/MIL-125(Ti)@Ti3C2 was investigated by the scavenging test. Additionally, Adsorption and catalytic degradation mechanisms were explored using X-Ray Photoelectron Spectroscopy (XPS) analysis. The cycling test proceeded on TiO2/MIL-125(Ti)@Ti3C2 for five succeeding Fenton-like degradation runs of CR dye. Ultimately, the Ti-based heterogeneous catalyst exhibited superior adsorption and Fenton-like degradation performance toward the anionic dye with a good recyclability feature.

Ni-doped ZnO nanorods/Ti3C2 MXene composites and their photocatalytic performance

Herein, composites based on Ni-doped ZnO nanorods and Ti3C2 MXene structure (Ni-ZnO NR/Ti3C2) were produced via a simple hydrothermal method for photocatalytic applications. Special attention was paid to their structural and optical properties. The composite exhibited a photocatalytic effectiveness of 88.2% in degrading methyl orange (MO) within a duration of 75 minutes when exposed to a xenon lamp. The enhancement of the catalytic activity was due to the one-dimensional ZnO nanostructure, the Ni doping, and the Schottky heterojunction is formed by the interface within ZnO and Ti3C2. Therefore, this work provides an effective strategy to fabricate metal oxide/MXene photocatalysts.

Harnessing Ti3C2-WS2 nanostructures as efficient energy scaffoldings for photocatalytic hydrogen generation

Two-dimensional (2D) Ti3C2 MXene have attracted a lot of attention as frontier materials for the development of effective photocatalysts that can transform solar energy into chemical energy, which is essential for water splitting to produce hydrogen. Here, we use first principle calculations to understand the structural, electronic, and vibrational features of a novel heterostructure comprising a monolayer of tungsten disulfide (WS2) and titanium carbide (Ti3C2) MXene. Our theoretical calculations revealed that the Ti3C2 maximizes the interfacial contact area with the WS2 monolayer creating a strong p–-d hybridization for the WS2/Ti3C2 heterostructure. As a result, a well-constructed Schottky junction is enabled, facilitating an interconnected electron pathway across the interface which is conducive for an efficient photocatalytic performance. Further, the experimentally designed WS2/Ti3C2 heterostructure and its photocatalytic activity based on the synergistic action between MXene and WS2 is investigated. Optical properties calculated are compared with experimental data derived from UV–Visible spectroscopy. The excellent conductivity and stability along with the light absorption in the visible region of WS2/Ti3C2 enhances the photocatalytic performance approaching photocurrent densities of ∼33 and 120 μA/cm2 in the HER and OER region, respectively. Overall, the present research not only improves our understanding of WS2/Ti3C2 heterostructure for an improved photocatalytic activity, but also provides an efficient method toward sustainable hydrogen production.

Solution-processed quantum dot short-wavelength infrared photodetectors via integrating 2D MXenes into electron transport layer

Solution-processed quantum dots (QDs) have attracted intensive attention in short-wavelength infrared (SWIR) photodetectors due to their excellent optical properties and tunable size-dependent bandgap. However, the intrinsic defects of the widely used ZnO electron-transport layer (ETL) and the inappropriate band alignment at the interface between the ETL and photoactive QDs inevitably impact the optoelectronic performance of the photodetector. Herein, a high-performance self-powered SWIR photodetector is developed by using 2D Ti3C2 MXenes to passivate the defects of ZnO ETL and to tailor the band alignment at the interface of the ETL/photoactive layer through interface engineering. As a result, the SWIR photodetectors demonstrate the ultra-high light-to-dark current (Ilight/Idark) ratio of ∼ 105 and the low dark current density of 8.33 × 10-4 mA/cm2, and the high specific detectivity (D*) of 1.99 × 1011 Jones at 0 V. By the systematic characterizations, it is proofed that 2D MXene can efficiently passivate defects in ZnO and optimize the alignment of energy levels between the ETL and photoactive layer, which will suppress the recombination of electrons and holes and eventually promote photogenerated carrier transfer at the interface and thus improve device performance. This work revealed that the high-performance solution-processed QD based SWIR photodetector enabled by interface engineering will promote the development of optoelectronic devices in the future.

Ti3C2 MXene/MoS2@AuNPs ternary nanocomposite for highly sensitive electrochemical detection of phoxim residues in fruits

Phoxim, extensively utilized in agriculture as an organothiophosphate insecticide, has the potential to cause neurotoxicity and pose human health hazards. In this study, an electrochemical enzyme biosensor based on Ti3C2 MXene/MoS2@AuNPs/AChE was constructed for the sensitive detection of phoxim. The two-dimensional multilayer structure of Ti3C2 MXene provides a robust framework for MoS2, leading to an expansion of the specific surface area and effectively preventing re-stacking of Ti3C2 MXene. Additionally, the synergistic effect of self-reduced grown AuNPs with MoS2 further improves the electrical conductivity of the composites, while the robust framework provides a favorable microenvironment for immobilization of enzyme molecules. Ti3C2 MXene/MoS2@AuNPs electrochemical enzyme sensor showed a significant response to phoxim in the range of 1 × 10−13 M to 1 × 10−7 M with a detection limit of 5.29 × 10−15 M. Moreover, the sensor demonstrated excellent repeatability, reproducibility, and stability, thereby showing its promising potential for real sample detection.

A novel iron oxide (Fe3O4)-laden titanium carbide (Ti3C2) MXene stacks for the efficient removal of tetracycline from aqueous solution

Fe3O4 has the advantages of unique magnetic stability and low biological toxicity, which can improve pollutants separation efficiency. MXenes are two-dimensional materials and easy surface functionalization that can provide suitable carriers for Fe3O4. In this work, we synthesized magnetic MXene composites by a one-pot method that relies on doping Fe3O4 particles onto Ti3C2 MXene nanosheets by heat treatment. The Fe3O4/Ti3C2 MXene was analyzed by SEM, XRD, FTIR and XPS techniques, which showed that the material has good tetracycline (TC) removal properties and magnetic separation ability. The results showed that the adsorption capacity of it was 46.42 mg g−1, and the removal efficiency of 0.06 g adsorbent for 50 mL of 30 mg L−1 TC could reach 92.1% in a wide pH range of 4–10, when the adsorption temperature was 25 °C, and the adsorption time was 3 h. The adsorption data were consistent with Langmuir and the proposed second-order kinetic model, and the thermodynamic experiments confirmed that the adsorption of TC was a monolayer physicochemical adsorption coexisting heat-trapping process (ΔH = 15.72 kJ mol−1). In addition, the adsorption of TC by Fe3O4/Ti3C2 MXene was attributed to the synergistic effect of electrostatic attraction, hydrogen bonding and π-π packing. In conclusion, the saturation magnetization of Fe3O4/Ti3C2 MXene is 27.3 emu/g and it can not only be separated from water using its strong magnetic properties to avoid secondary contamination, but also can be used as a promising material to effectively remove antibiotics from aqueous media.

Optimizing the Synthesis of Titanium Carbide-Bismuth Oxide for Enhanced Antimicrobial Properties.

Background The two-dimensional MXene, known as titanium carbide (Ti₃C₂), is characterized by its substantial interlayer spacing, extensive surface area, hydrophilic nature, exceptional thermal stability, and outstanding electrical conductivity. These distinctive attributes render Ti₃C₂ an ideal candidate for detecting target analytes and immobilizing biomolecules. Bismuth oxide (Bi₂O₃), an essential compound of bismuth, frequently acts as a foundational element in bismuth chemistry. Its applications are diverse, from fireworks to oxygen gas sensors and solid oxide fuel cells, with particular emphasis on its behaviour under elevated temperatures and pressures. Notably, phase transitions to various polymorphs, which remain metastable at room temperature, have been documented under these conditions, indicating potential for numerous applications. Integrating MXene with Bi₂O₃ composites holds significant promise for advancements in energy-related electronics, sensing technologies, and photocatalytic processes. Objective To optimize the synthesis of titanium carbide-bismuth oxide (Ti₃C₂-Bi₂O₃) nanoparticles to enhance their antimicrobial activity by identifying the best synthesis conditions and assessing their effectiveness against various microbial pathogens. Materials and methods The preparation of Ti₃C₂ MXene involves dissolving lithium fluoride in hydrochloric acid, followed by Ti₃AlC₂ and stirring at 40°C for 48 hours. The resulting pellet is then dispersed in ultrapure water and centrifuged to obtain the MXene dispersion. Bi₂O₃ nanoparticles are prepared by preparing bismuth nitrate pentahydrate in nitric acid and adding sodium hydroxide to adjust the pH. The resulting white precipitate is filtered, washed, and dried before being calcined at 400°C for two hours to produce Bi₂O₃ nanoparticles. The Ti₃C₂-Bi₂O₃ composite is synthesized by adding Bi(NO₃)₃ solution to a 5 mg/mL Ti₃C₂Tx MXene solution. The reaction solution is heated to 160°C, and the resulting black powder is labelled as x% Bi₂O₃/MXene. The antimicrobial efficacy of the nanoparticles is assessed using the disk diffusion method. The zones of inhibition are measured and analyzed as indicators of antimicrobial activity. Results The scanning electron microscopy (SEM) analysis revealed the presence of Bi₂O₃ particles alongside Ti₃C₂​​​​​​​ nanosheets, while the X-ray diffraction (XRD) analysis and energy-dispersive X-ray spectroscopy (EDS) confirmed the high crystallinity of the compound. Furthermore, the compound was determined to be impurity-free and demonstrated antimicrobial properties. Conclusion The XRDanalysis confirms the effective integration of various materials and the existence of crystalline phases. SEMprovides insights into the morphology and organization of particles within sheets, whereas EDSassesses the elemental composition and its uniform distribution. These studies demonstrate the synthesis of Ti₃C₂-Bi₂O₃​​​​​​​ composites, suggesting their potential for usage in applications involving antimicrobial action.

Effect of oxygen-substituted lattice carbon in Ti3C2 MXene as anchoring material for Li-S battery: DFT calculations and experiments

Electrochemical processes involving the adsorption/desorption of polysulfides are usually related to the composition of adsorbed-sulfur electrode material. Here, we investigate the moderate influence of non-metallic O and C elements on anchoring property towards lithium polysulphides (LiPSs), whereby the adsorption behavior of 2D-Ti3C2 MXene with continuous O-substitution into C site is analyzed via density functional theory (DFT) calculations in concerning of reported inevitable oxygen in the lattice. The introduction of O into 2D-Ti3C2 lattice reduces the density of states of Ti elements near the Fermi level, thus weakening the Ti-S binding interaction. Ti3C2 MXene with C/O ratio of 3:1 (Ti3C2-C12O4 model) exhibits moderate adsorption superior to other compositions, where the calculated binding energies of S8 and Li2Sn (n = 8, 6, 4) are −2.88, −2.57, −2.31 and −2.19 eV atom−1, respectively. The substitution of O atom theoretically hinders the transfer of Li+ and reduces the energy barrier of S-migration, thus promoting the anchoring and transformation of LiPSs. Notably, consistent result is obtained from the comparative study on electrochemical performance of titanium oxycarbide with precisely different C/O ratios as alternative, considering the unpractical controlling of O-content in 2D-Ti3C2 and the homologous crystal structure. Titanium oxycarbide with C/O ratio of 3:1 (Ti(C,O)-C12O4) as anchoring material in Li-S battery exhibits a superior initial specific capacity of 841 mAh/g at 1C and fasten ion diffusion coefficients (1.92 cm2 s−1 and 2.94 cm2 s−1). This study suggest attention on regulatory effect of non-metallic elements in lattice instead of surface towards performance optimization of titanium-carbide-based material as host for sulfur cathode utilized in Li-S battery.

Novel synthesis of Ti3C2 MXene/ZnO/CdSe for sonoelectron and photoelectron triggered synergetic sonophotocatalytic degradation with various antibiotics

A straightforward and precise method was employed to generate Ti3C2 MXene/ZnO/CdSe photocatalysts by a simple synthesis process involving calcination at a temperature of 400 °C. Optical, structural, morphology, microstructure, and compositional properties of these catalysts were characterized. Results demonstrated that the presence of ZnO and CdSe doping sustained their existence inside the Ti3C2 MXene structure. Effects of catalyst powder, pollutant powder, and different degrading methods such as sonophotocatalytic, sonocatalytic, and photocatalytic methods on various antibiotic pollutants were then compared. The degradation efficiencies of sonophotocatalytic method were found to be highly efficient, resulting of 99.99, 99.98, and 99.90 % for ciprofloxacin, amoxicillin, and ofloxacin, respectively. Analysis of scavenger effect also illustrated the deterioration of ciprofloxacin and amoxicillin, suggesting that superoxide radicals (O2−) had a substantial role in the sonophotocatalytic degradation process. Based on data obtained for ofloxacin, it was clear that the existence of holes (h+ quencher) affected the deterioration of ofloxacin in the system. Ti3C2 MXene/ZnO/CdSe had a performance in electrochemical sensing. Limits of detection (LODs) for ciprofloxacin, amoxicillin, and ofloxacin were 39.29, 4.49, and 13.04 ppm, respectively. Limits of quantification (LOQs) for ciprofloxacin, amoxicillin, and ofloxacin were 119, 13.61, and 39.52 ppm, respectively. Efficient degradation of pollutants using visible light can be achieved by employing straightforwardly manufactured Ti3C2 MXene/ZnO/CdSe photocatalysts, making them a practical and promising option.

FeF3·0.33H2O nanoparticles decorated Ti3C2 MXene as high-performance bifunctional sulfur host for lithium‑sulfur batteries

Lithium‑sulfur batteries are deemed as a potential next-generation energy storage system, but their development is hindered by the shuttle effect of lithium polysulfides. Design and synthesis of multifunctional sulfur host materials are expected to adsorb lithium polysulfides and catalyze their conversion during the lithiation process, thereby suppressing the shuttle effect. In this work, FeF3·0.33H2O nanoparticles is in situ grown on the surface of Ti3C2 nanosheets (FeF3@Ti3C2) and used as the bifunctional sulfur host for lithium‑sulfur batteries. Ti3C2 nanosheets not only provide two-dimensional (2D) conductive substrate for sulfur, but also strongly adsorb lithium polysulfides and suppress the shuttle effect. Meanwhile, FeF3 nanoparticles can accelerate the conversion reaction of lithium polysulfides, which also contributes to inhibiting the shuttle of lithium polysulfides. In addition, decorating Ti3C2 nanosheets with FeF3 nanoparticles can prevent the stacking of Ti3C2 nanosheets and enhance the interaction between Ti3C2 and lithium polysulfides. Therefore, sulfur-loaded FeF3@Ti3C2 (FeF3@Ti3C2@S) displays excellent electrochemical performance, such as a high reversible capacity of 687 mAh g−1 at 2C after 1000 cycles, and the capacity decay rate is only 0.023 %. This work paves a simple way for improving the performance of Ti3C2 as the sulfur host and expanding its application in lithium‑sulfur batteries.