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Evaluating the delamination process in the synthesis of MXenes (2D transition metal carbides and nitrides) is critical for their development and applications. However, the preparation of large defect‐free MXene flakes with high yields is challenging. Here, a power‐focused delamination (PFD) strategy is demonstrated that can enhance both the delamination efficiency and yield of large Ti3C2Tx MXene nanosheets through repetitive precipitation and vortex shaking processes. Following this protocol, a colloidal concentration of 20.4 mg mL–1 of the Ti3C2Tx MXene can be achieved after five PFD cycles, and the yield of the basal‐plane‐defect‐free Ti3C2Tx nanosheets reaches 61.2%, which is 6.4‐fold higher than that obtained using the sonication–exfoliation method. Both nanometer‐thin devices and self‐supporting films exhibit excellent electrical conductivities (≈25 000 and 8260 S cm‐1 for a 1.8 nm thick monolayer and 11 µm thick film, respectively). Hydrodynamic simulations reveal that the PFD method can efficiently concentrate the shear stress on the surface of the unexfoliated material, leading to the exfoliation of the nanosheets. The PFD‐synthesized large MXene nanosheets exhibit superior electrical conductivities and electromagnetic shielding (shielding effectiveness per unit volume: 35 419 dB cm2 g–1). Therefore, the PFD strategy provides an efficient route for the preparation of high‐performance single‐layer MXene nanosheets with large areas and high yields. A new method for the preparation of large 2D Ti3C2Tx MXene nanosheets is reported. The method is based on conventional etching followed by repetitive precipitation and vortex shaking process, which efficiently transfer the mechanical energy for exfoliation. Consequently, large defect‐free sheets that show an excellent electromagnetic shielding performance are produced with high yields.

Based on calculations of the local stress field under external loading, a strength model for a micro-cell with interface delamination is established. A theoretical formula for calculating the failure stress is derived. The relationship between the microstructure of eutectic ceramics and failure stress is analyzed. The results show that micro-cell azimuth, delamination length, and the volume fraction of interface delamination have significant effects on the strength of eutectic ceramics.

Since the first report on Ti3C2Tx in 2011, the family of two-dimensional transition metal carbides, nitrides, and carbonitrides (MXenes) has increased substantially to include single and multi-element MXenes, with many more yet to be synthesized but predicted to possess attractive properties. To synthesize these elusive MXenes as well as to improve and scale up the manufacturing of known MXenes, a deeper mechanistic understanding of their synthesis processes is necessary, from the precursors to the etching–exfoliation and final intercalation–delamination steps. Here we examine computational modelling and in situ and ex situ characterization data to rationalize the reactivity and selectivity of MXenes towards various common etching and delamination methods. We discuss the effects of MAX phases, the predominant precursor, and other non-MAX layered materials on MXene synthesis and their resultant properties. Finally, we summarize the parameters behind successful (and unsuccessful) etching and delamination protocols. By highlighting the factors behind each step, we hope to guide the future development of MXenes with improved quality, yield and tunable properties.MXenes are 2D materials with a rich chemistry and applications in energy storage, electronics and biomedicine. This Review discusses various MXene syntheses—from layered precursors to single-layer 2D flakes—including principles behind these methods and synthesis–structure–property relationships.

Due to easy re-stacking, low yield of few-layered MXenes (f-MXenes), the applications of MXenes are mainly restricted in multi-layered MXenes (m-MXenes) state. Although f-MXenes can be prepared from m-MXenes, after exfoliation process, a mass of sediments which are still essentially compact MXenes are usually directly discarded, leading to low utilization of raw m-MXenes. Herein, a classified preparation strategy is adopted to exploit the raw m-MXenes and traditional MXenes sediments, taking multi-layered Ti 3 C 2 T x MXene as an example. Via rational delamination and subsequent treatment to Ti 3 C 2 T x sediments, we succeed in achieving classified and large-scale preparation of various Ti 3 C 2 T x MXene derivatives, including few-layered Ti 3 C 2 T x (f-Ti 3 C 2 T x ) powders, f-Ti 3 C 2 T x films, and Ti 3 C 2 T x MXene-derived nanowires with heterostructure of potassium titanate and Ti 3 C 2 T x . We demonstrate the necessity of “step-by-step delamination” towards traditional Ti 3 C 2 T x sediments to improve the yield of f-Ti 3 C 2 T x from 15% to 72%; the feasibility of “solution-phase flocculation (SPF)” to fundamentally solve the re-stacking phenomenon, and oxidation degradation issues of f-Ti 3 C 2 T x during storage; as well as the convenience of SPF to deal with time-consuming issues of fabricating Ti 3 C 2 T x films. What’s more, alkali-heat treatment of final Ti 3 C 2 T x sediments turns waste into treasure of Ti 3 C 2 T x -derived nanowires, leading to 100% utilization of raw Ti 3 C 2 T x . The content of one-dimensional (1D) nanowires in the hybrids can be adjusted by controlling alkalization time. The 3D architecture heterostructure composed of 1D nanowires and 2D nanosheets exhibits gorgeous application potential. This work can expand preparation and application of various MXenes derivatives, promoting process of various MXenes.

Tungsten co-deposited layers in fusion devices are a significant potential source of plasma-contaminating dust. This study investigates the mechanisms of dust release from helium–tungsten (He–W) and deuterium–tungsten (D–W) layers under high-density steady-state plasma and ELM-like plasma pulse superposition. High-speed imaging revealed different emission behaviors: the D–W layer, featuring pre-existing blisters, released dust immediately upon plasma exposure, while the He–W layer showed a delayed emission requiring damage accumulation from several pulses. Post-mortem SEM analysis confirmed distinct surface exfoliation corresponding to these behaviors. The immediate release of D–W dust was identified as the rupture of inherently fragile blisters. In contrast, the delayed release of He–W dusts resulted from subsurface flaking, initiated by horizontal cracks forming from the interconnection of internal nano-cavities. Both layers produced substantial dust, leading to much higher erosion rates than that of pristine tungsten. These results demonstrate that the trapped gas species fundamentally dictates the co-deposited layer’s microstructure and subsequent dust emission pathway, establishing these layers as a critical and rapid dust source under transient plasma loads.

Developing ultrahigh-strength steels that are ductile, fracture resistant, and cost effective would be attractive for a variety of structural applications. We show that improved fracture resistance in a steel with an ultrahigh yield strength of nearly 2 gigapascals can be achieved by activating delamination toughening coupled with transformation-induced plasticity. Delamination toughening associated with intensive but controlled cracking at manganese-enriched prior-austenite grain boundaries normal to the primary fracture surface dramatically improves the overall fracture resistance. As a result, fracture under plane-strain conditions is automatically transformed into a series of fracture processes in “parallel” plane-stress conditions through the thickness. The present “high-strength induced multidelamination” strategy offers a different pathway to develop engineering materials with ultrahigh strength and superior toughness at economical materials cost.

The Anatolian Plateau, currently experiencing rapid uplift and westward escape, records both the termination of oceanic subduction and the conversion to continental collision. The crustal response to the transition of the subduction environment from eastern to western Anatolia can be inferred by the seismic velocity and attenuation structures. With this study, we construct a broadband Lg‐wave attenuation model for the Anatolian Plateau and use it to constrain lateral crust heterogeneities linked to this transition. Crustal Lg attenuation links late Cenozoic magmatism with asthenospheric upwelling by characterizing the lithospheric thermal structure. The widely distributed strong attenuation observed in eastern Anatolia may be related to the crustal partial melting due to mantle upwelling after the delamination and subsequent break‐off of the Bitlis slab. Lithospheric dripping in central Anatolia likely facilitates the mantle flows through the window between the Cyprus and Aegean slabs, which results in the piecemeal low QLg${Q}_{\\mathit{Lg}}$anomaly in central Anatolia. Plain Language Summary Different parts of the Anatolian Plateau are in different evolution stages between oceanic subduction and continental collision and currently undergoing plateau uplift and tectonic escape. The regional seismic velocity and attenuation can be used to characterize crustal partial melting and lateral heterogeneity, which can further identify the underlying subduction process. In this study, we construct a high‐resolution broadband Lg‐wave attenuation model for the Anatolian Plateau. Strong Lg attenuation in Anatolia correlates well with late Cenozoic magmatism distributions and can be an indicator of high temperature or partial melting in the crust. Combined with previous studies, we suggest that the mantle upwelling induced by the delamination of the Bitlis slab is likely reworking the crust in eastern Anatolia and is the cause of widespread thermal anomalies there. The lithospheric dripping process in central Anatolia may facilitate the mantle flows through the window between the Cyprus and Aegean slabs, and results in a piecemeal low QLg${Q}_{\\mathit{Lg}}$anomaly pattern in central Anatolia. Key Points A high‐resolution broadband Lg‐wave attenuation model is constructed for the Anatolian Plateau Widespread strong attenuation in the eastern Anatolian crust is likely related to slab delamination The circular‐shaped attenuation anomaly may result from slab tearing and lithospheric dripping beneath central Anatolia

In order to analyze the causes of delamination cracking of 400 HB class TiC strengthened antifriction steel during cold bending, the morphology, chemical composition and distribution of non-metallic inclusions in the central part of the thickness (1/2 thickness) and other parts of the cracked sample were analyzed by optical microscope, scanning electron microscope and energy dispersive spectrometer (SEM-EDS), electron probe (EPMA). The results indicate that there are large-sized inclusions composed mainly of oxides of elements such as Ti, Si, Mn, which extend along the rolling direction and have a length exceeding 200 μm at the 1/2 thickness of the sample. In other parts of the sample, the inclusions are mainly particles of Ti(C, N), Al 2 O 3 and other types, with relatively small sizes and uniform distribution. The large inclusions with a length exceeding 200 μm, located at 1/2 thickness, are the direct cause of cold bending delamination cracking.

MXenes are a large family of two-dimensional materials that have attracted attention across many fields due to their desirable optoelectronic, biological, mechanical and chemical properties. There currently exist many synthesis procedures that lead to differences in flake size, defects and surface chemistry, which in turn affect their properties. Herein, we describe the steps to synthesize Ti 3 C 2 T x —the most important and widely used MXene, from a Ti 3 AlC 2 MAX phase precursor. The procedure contains three main sections: synthesis of Ti 3 AlC 2 MAX, wet chemical etching of the MAX in hydrofluoric acid/HCl solution to yield multilayer Ti 3 C 2 T x and its delamination into single-layer flakes. Three delamination options are described; these use LiCl, tertiary amines (tetramethyl ammonium hydroxide/ tetrabutyl ammonium hydroxide) and dimethylsulfoxide respectively. These procedures can be adapted for the synthesis of MXenes beyond Ti 3 C 2 T x . The MAX phase synthesis takes about 1 week, with the etching and delamination each requiring 2 d. This protocol requires users to have experience working with hydrofluoric acid, and it is recommended that users have experience with wet chemistry and centrifugation; characterization techniques such as X-ray diffraction and particle size analysis are also essential for the success of the protocol. While alternative synthesis methods, such as minimally intensive layer delamination, are desirable for certain MXenes (such as Ti 2 CT x ) or specific applications, this protocol aims to standardize the more commonly used hydrofluoric acid/HCl etching method, which produces Ti 3 C 2 T x with minimal concentration of defects and the highest conductivity and serves as a guideline for those working with MXenes for the first time. Key points MXenes are two-dimensional materials, the best known of which is Ti 3 C 2 T x . Many diverse and unique properties have been described for MXenes, but it is difficult to compare the data because their physical characteristics depend on their synthesis. This protocol provides a detailed guideline for the synthesis of a Ti 3 AlC 2 MAX phase precursor, wet chemical etching of MAX to yield multilayer Ti 3 C 2 T x and its delamination into single-layer flakes. MXenes are two-dimensional materials with diverse optoelectronic, biological, mechanical and chemical properties. This protocol describes how to prepare single-layer flakes of Ti 3 C 2 T x , the most important and widely used MXene, from a Ti 3 AlC 2 MAX phase precursor.

This study aims to reveal the effect and correlation of delamination size and defect shape for using infrared thermography (IRT) through FE modeling to enhance the reliability and applicability of IRT for effective structural inspections. Regarding the effect of delamination size, it is observed that the temperature difference between sound and delaminated area ( Δ T) increases as the size of delamination increases; however, Δ T converges to a certain value when the area is 40 × 40 cm and the thickness is 1 cm. As for the shape of delamination, it can be assumed that if the aspect ratio which is the ratio of the length of the shorter side to the longer side of the delamination is more than 25%, Δ T of any delaminations converges to Δ T of the same area of a square/circular-shaped delamination. Furthermore, if the aspect ratio is 25% or smaller, Δ T becomes smaller than the Δ T of the same area of a square/circular-shaped delamination, and it is getting smaller as the ratio becomes smaller. Furthermore, this study attempts to estimate depths of delaminations by using IRT data. Based on the correlation between the size of delamination and the depth from the concrete surface in regard to Δ T, it was assumed that it was possible to estimate the depth of delamination by comparing Δ T from IRT data to Δ T at several depths obtained from FE model simulations. Through the investigation using IRT data from real bridge deck scanning, this study concluded that this estimation method worked properly to provide delamination depth information by incorporating IRT with FE modeling.