Ti3C2Tx MXene Polymer Composites for Anticorrosion: An Overview and Perspective

Functionalized MXene composites for protection on metals in electric power

Metals used in electric power suffer from icing, wear, and corrosion problems, resulting in high energy consumption, economic losses, security risks, and increased CO2 emission. To address these problems, researchers have turned to two-dimensional (2D) transition metal carbide or nitride (MXene) materials, which possess strong near-infrared adsorption, photothermal conversion, shear ability, low friction coefficient, and impermeability. These properties make MXene a promising candidate for surface protection on metals in electric power, including anti-icing, anti-wear, and anti-corrosion applications. However, the comprehensively protective ability and the promising application of MXene in electric power have not yet been reported. In this review, recent progress in MXene-based composites for anti-icing, anti-wear, and anti-corrosion in electric power is summarized to understand the protective mechanisms and the promising applications. First, the chemical and structure of MXene are briefly introduced, followed by a summary of its intrinsic properties. Next, the latest research on deicing MXene composite coatings, anti-wear MXene-based composites and coatings, and anti-corrosive MXene coatings, along with the corresponding mechanisms, is discussed. Finally, the challenges and opportunities of MXene-based composites in electric power are highlighted. This review provides guidance for understanding the comprehensively protective abilities of MXene and rationally designing MXene-based materials used in electric power.

Supramolecular structure@MXenes for photocatalytic applications - a review

Recently, supramolecules have emerged as innovative and eco-friendly options for photocatalytic applications due to their tunable porous structures and photophysical properties. However, their low thermal stability and chemical stability pose a significant challenge. To address this, combining supramolecules with more stable materials like MXenes, which have a low Fermi energy level, is a useful strategy, in which they can form heterostructures that enhance stability and improve photocatalytic activity. The synthesis process, whether through in situ or post-synthesis modifications, plays a crucial role in controlling the formation of both covalent and non-covalent interactions, as well as the morphology of the heterostructures. These interactions and the resulting morphology significantly influence the recombination and separation of charge carriers (electron-hole pairs), ultimately affecting the stability and recyclability of the heterostructures in photocatalytic applications. In this review, we discuss the importance of supramolecule/MXene heterostructures, detailing their synthesis and morphology, as well as the mechanisms involved in various applications.

In situ growth of two-dimensional MXene/Nano-copper metal-organic framework composites for antimicrobial applications in epoxy coatings

Marine biofouling and corrosion are serious impediments to the promotion and development of the marine industry. The short service life and limited application of single coatings have greatly increased the economic burden on the industry. The development of multi-functional composite coatings has become a particularly pressing issue. The combination of Cu-BTC and Ti3C2Tx as a specific resin filler represents a new strategy (Ti3C2Tx@Cu-BTC@EP). HAADF-STEM, PXRD and XPS were used to verify the successful synthesis of the materials. Ti3C2Tx@Cu-BTC@EP was able to achieve 100 % lethality of E. coli under the condition of light exposure within 24 h. In addition, the impedance modulus of the coating in the low-frequency range was increased by about 3.15 times compared to the blank group with the addition of 1 wt% filler, reaching as high as 7.06 × 108 Ω. Overall, the novel Ti3C2Tx@Cu-BTC@EP composite coating is expected to promote new advances in epoxy resin research.

Surface-Modification Strategy to Produce Highly Anticorrosive Ti3C2Tx MXene-Based Polymer Composite Coatings: A Mini-Review

MXenes are a group of novel two-dimensional (2D) materials with merits such as large specific surface area, abundant surface-functional groups, high chemical activity, excellent mechanical properties, high hydrophilicity, and good compatibility with various polymers. In recent years, many novel high-performance organic anticorrosion coatings using MXenes as nanofillers have been reported and have attracted widespread attention. As the first successfully prepared MXene material, Ti3C2Tx is the most extensively studied and typical member of the MXene family. Therefore, it is taken as the representative of its family, and the status of Ti3C2Tx MXene/epoxy resin (EP) and MXene/waterborne polyurethane (WPU) polymer anticorrosive composite coatings is reviewed. Firstly, the structure, characteristics, and main synthesis methods of MXenes are briefly introduced. Then, the latest progress of four surface-modification strategies to improve the dispersion, compatibility, stability, and anti-aggregation properties of MXenes, namely functionalization grafting, orientation regulation, heterostructure nanocomposite design, and stabilization and greening treatment, are analyzed and summarized. Finally, the current challenges and future opportunities regarding MXene-based corrosion-resistant organic composite coatings are discussed prospectively.

A comprehensive overview of recent progress in MXene-based polymer composites: Their fabrication processes, advanced applications, and prospects

MXenes are a group of 2D transition metal carbonitrides, nitrides and carbides that have become widely recognized as useful materials since they were first discovered in 2011. MXenes, with their exceptional layered structures and splendid external chemistries, have excellent electrical, optical, and thermal properties, making them suitable for catalysis, biomedical uses, environmental remediation, energy storage, and EMI shielding. Over forty MXene compounds with surface terminations like hydroxyl, oxygen, or fluorine are hydrophilic and easily integrated into various applications. Advanced synthesis methods, including selective etching and etchant modifications, have broadened MXene surface chemistries for customized mechanical, thermal, and electrical applications. Integrating MXenes into polymer composites has demonstrated notable promise, enhancing the host polymers' electrical conductivity, thermal stability and mechanical strength. The MXene-polymer composites demonstrate remarkable prospective on behalf of advanced purposes, including flexible electronics, high-performance EMI shielding materials, and lightweight structural components. MXenes have the desirable characteristic of being able to create flexible and translucent films, as well as improve the properties of polymer matrices. This makes them very suitable for use in advanced technological applications. This review summarizes MXene research, methods, and insights, highlighting key discoveries and future directions. This also highlights the importance of ongoing research to fill in the gaps in current knowledge and improve the practical uses of MXenes.

Advancements in MXene-based composites for electronic skins

MXenes are a class of two-dimensional (2D) materials that have gained significant attention in the field of electronic skins (E-skins). MXene-based composites offer several advantages for E-skins, including high electrical conductivity, mechanical flexibility, transparency, and chemical stability. Their mechanical flexibility allows for conformal integration onto various surfaces, enabling the creation of E-skins that can closely mimic human skin. In addition, their high surface area facilitates enhanced sensitivity and responsiveness to external stimuli, making them ideal for sensing applications. Notably, MXene-based composites can be integrated into E-skins to create sensors that can detect various stimuli, such as temperature, pressure, strain, and humidity. These sensors can be used for a wide range of applications, including health monitoring, robotics, and human-machine interfaces. However, challenges related to scalability, integration, and biocompatibility need to be addressed. One important challenge is achieving long-term stability under harsh conditions such as high humidity. MXenes are susceptible to oxidation, which can degrade their electrical and mechanical properties over time. Another crucial challenge is the scalability of MXene synthesis, as large-scale production methods need to be developed to meet the demand for commercial applications. Notably, the integration of MXenes with other components, such as energy storage devices or flexible electronics, requires further developments to ensure compatibility and optimize overall performance. By addressing issues related to material stability, mechanical flexibility, scalability, sensing performance, and power supply, MXene-based E-skins can develop the fields of healthcare monitoring/diagnostics, prosthetics, motion monitoring, wearable electronics, and human-robot interactions. The integration of MXenes with emerging technologies, such as artificial intelligence or internet of things, can unlock new functionalities and applications for E-skins, ranging from healthcare monitoring to virtual reality interfaces. This review aims to examine the challenges, advantages, and limitations of MXenes and their composites in E-skins, while also exploring the future prospects and potential advancements in this field.

WS2-intercalated Ti3C2Tx MXene/TiO2-stacked hybrid structure as an excellent sonophotocatalyst for tetracycline degradation and nitrogen fixation

Designing a heterostructure nanoscale catalytic site to facilitate N2 adsorption and photogenerated electron transfer would maximize the potential for photocatalytic activity and N2 reduction reactions. Herein, we have explored the interfacial TiO2 nanograins between the Ti3C2TxMXene-WS2 heterostructure and addressed the beneficial active sites to expand the effective charge transfer rate and promote sonophotocatalytic N2 fixation. Benefiting from the interfacial contact and dual heterostructure interface maximizes the photogenerated carrier separation between WS2 and MXene/TiO2. The sonophotocatalytic activity of the MXene@TiO2/WS2 hybrid, which was assessed by examining the photoreduction of N2 with ultrasonic irradiation, was much higher than that of either sonocatalytic and photocatalytic activity because of the synergistic sonocatalytic effect under photoirradiation. The Schottky junction between the MXene and TiO2 on the hybrid MXene/TiO2-WS2 heterostructure resulted in the sonophotocatalytic performance through effective charge transfer, which is 1.47 and 1.24 times greater than MXene-WS2 for nitrogen fixation and pollutant degradation, respectively. Under the sonophotocatalytic process, the MXene/TiO2-WS2 heterostructure exhibits a decomposition efficiency of 98.9 % over tetracycline in 90 min, which is 5.46, 1.73, and 1.10 times greater than those of sonolysis, sonocatalysis, and photocatalysis, respectively. The production rate of NH3 on MXene/TiO2-WS2 reached 526 μmol g-1h-1, which is 3.17, 3.61, and 1.47 times higher than that of MXene, WS2, and MXene-WS2, respectively. The hybridized structure of MXene-WS2 with interfacial surface oxidized TiO2 nanograins minimizes the band potential and improves photocarrier use efficiency, contributing directly to the remarkable catalytic performance towards N2 photo fixation under visible irradiation under ultrasonic irradiation. This report provides the strategic outcome for the mass carrier transfer rate and reveals a high conversion efficiency in the hybridized heterostructure.

Novel Strain Engineering Combined with a Microscopic Pore Synergistic Modulated Strategy for Designing Lattice Tensile-Strained Porous V2C-MXene for High-Performance Overall Water Splitting

Transition metal carbon/nitride (MXene) holds immense potential as an innovative electrocatalyst for enhancing the overall water splitting properties. Nevertheless, the re-stacking nature induced by van der Waals force remains a significant challenge. In this work, the lattice tensile-strained porous V₂C-MXene (named as TS₍₂₄₎-P₍₅₀₎-V₂C) is successfully constructed via the rapid spray freezing method and the following hydrothermal treatment. Besides, the influence of lattice strain degree and microscopic pores on the catalytic ability is reviewed and explored systematically. The lattice tensile strain within V₂C-MXene could widen the interlayer spacing and accelerate the ion transfer. The microscopic pores could change the ion transmission path and shorten the migration distance. As a consequence, the obtained TS₍₂₄₎-P₍₅₀₎-V₂C shows extraordinary hydrogen evolution reaction and oxygen evolution reaction activity with the overpotential of 154 and 269 mV, respectively, at the current density of 10 mA/cm², which is quite remarkable compared to the MXene-based electrocatalysts. Moreover, the overall water splitting device assembled using TS₍₂₄₎-P₍₅₀₎-V₂C as both anode and cathode demonstrates a low cell voltage requirement of 1.57 V to obtain 10 mA/cm². Overall, the implementation of this work could offer an exciting avenue to overcome the re-stacking issue of V₂C-MXene, affording a high-efficiency electrocatalyst with superior catalytic activity and desirable reaction kinetics.