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Booming sophisticated robotics and prosthetics put forward high requirements on soft conductive materials that can bridge electronics and biology, those soft conductive materials should imitate the mechanical properties of biological tissues and build information transmission networks. Until now, it remains a great challenge to handle the trade‐off among ease of preparation, high conductivity, processability, mechanical adaptability, and external stimuli responsiveness. Herein, a kind of readily prepared and processed multifunctional MXene nanocomposite hydrogel is reported, which is prepared via the fast gelation of cationic monomer initiated by delaminated MXene sheets. The gelation time can be adjusted (several seconds to minutes) based on the MXene loadings. By adjusting the MXene ratio, the resulting nanocomposites are ultrastretchable (>5000%), three‐dimensional (3D) printable, and show outstanding mechanical and electrical self‐healing. As expected, the integration of multifunctional systems onto various substrates (e.g., gloves and masks) is further demonstrated via 3D printing and could achieve diverse sensory capabilities toward strain, pressure, and temperature, showing great prospects as smart flexible electronics. [ABSTRACT FROM AUTHOR]

Incorporating conductive and porous components as pillaring materials into the interlayers of two‐dimensional (2D) materials offers a solution to the restacking issue and enables the creation of multifunctional hetero‐superstructures. Here, multilayer MXene superlattices intercalated with monolayer mesoporous carbon frameworks (MMCFs) are synthesized by colloidal co‐assembly of MXene Ti3C2Tx nanosheets and Fe3O4 nanoparticles. The intercalated MMCFs not only increase interlayer spacing and create porous channels for fast mass transport but also act as conductive pillars to facilitate electron transfer along the z‐direction. These unique structural features allow for the full utilization of unilamellar MXene, making the resulting Ti3C2Tx/MMCF superlattices particularly suitable for capacitive energy storage in organic electrolytes containing bulky ions. As a demonstration, supercapacitors made from Ti3C2Tx/MMCFs exhibit a volumetric capacitance of 317 F cm−3 in a tetraethylammonium tetrafluoroborate/propylene carbonate electrolyte. Furthermore, on‐chip micro‐supercapacitors (MSCs) fabricated from Ti3C2Tx/MMCFs, using the ionic liquid 1‐ethyl‐3‐methylimidazolium tetrafluoroborate as an electrolyte, achieve an areal energy density of 0.10 mWh cm−2, surpassing that of most state‐of‐the‐art MXene‐based MSCs developed to date. This study not only highlights the significant potential of Ti3C2Tx/MMCFs for efficient capacitive energy storage in organic electrolytes but also introduces a new method for synthesizing 2D porous hetero‐superstructures for various applications. [ABSTRACT FROM AUTHOR]

Flotation is a physical and chemical process that uses the difference between mineral surface properties to separate valuable minerals from worthless minerals through the attachment of bubbles. The visual information of the flotation foam surface can reflect the flotation effect and will be closely related to the flotation conditions, directly indicating the degree of mineralization of the foam layer. Considering the problem that coal slurry foam images are difficult to segment due to the mutual adhesion of bubbles and fuzzy boundaries, in this work, we proposed a new and effective segmentation algorithm for extracting coal slurry flotation foam edge information. Based on the encoder and decoder structure, a selective multi-branch input segmentation deep neural network model was designed. We evaluated the proposed method and model using a self-built coal slurry foam image segmentation dataset. The intersection over union, mean intersection over union, and PA evaluation indicators of this method increased by 12.8376%, 7.2716%, and 1.457%, respectively, compared with those of the U-Net model. The experimental results showed that the selective branch segmentation network model had high accuracy and robustness in extracting coal slurry bubble edge information, and it could effectively solve the problem of difficult segmentation of coal slurry foam images. This study provided a foundation for optimizing flotation process parameters and realizing intelligent flotation site parameters. [ABSTRACT FROM AUTHOR]

The lifespan of proton‐exchange membrane fuel cells heavily relies on the durability of the carbon support of cathode catalysts. However, commercial carbon supports like ketjenblack (KB) and Vulcan carbon (VC) face the challenge of balancing porosity, surface area, and electrochemical stability. To address this issue, a 3D porous wrinkled graphitic carbon (PWGC) is designed and synthesized using a catalyst‐free, plasma‐enhanced chemical vapor deposition approach. The resulting PWGC possesses a hierarchically porous structure with a high surface area, a high degree of graphitization, and exceptional corrosion resistance. As a result, the Pt/PWGC catalysts with the use of PWGC as the carbon support demonstrate superior high potential stability compared to those made with KB and VC as the carbon support. Additionally, a sacrificial layer strategy is introduced to further reduce PWGC corrosion, resulting in Pt@C/PWGC catalysts that show significantly improved durability in membrane electrode assembly tests. After 5K voltage cycles from 1.0 to 1.5 V, the retention of electrochemically active surface area approaches 56.8%, surpassing the 23.6% retention of commercial Pt/C catalysts tested under the same conditions. [ABSTRACT FROM AUTHOR]

The exceptional properties of 2D transition metal carbides and nitrides (MXene) have led to numerous promising applications. However, the performance of MXene is often dependent on the size of the flakes, and obtaining large‐sized, high‐quality MXene flakes remains challenging. Herein, a carbon nanotube (CNT)‐assisted exfoliation strategy is introduced, which significantly improves the yield of large‐flake MXene while entirely transforming the centrifugation residues into small‐flake MXene, resulting in waste‐free synthesis of MXene. The average size of the obtained MXene flakes can reach over 10 and 0.7 µm for the two populations, respectively. Additionally, the capacitive performance of MXene can be greatly enhanced with a small amount of CNTs. As a proof of concept, a planar interdigital micro‐supercapacitor with heterogeneous layers assembled by large‐ and small‐flake MXene simultaneously exhibits outstanding synergistic enhancement in volumetric capacitance (1072 F cm⁻3) and energy density (53.5 mWh cm⁻3). This CNT‐assisted method provides explicit directions for achieving the ideal utilization of MXene, improving the yield of large flakes while making judicious use of waste, to meet specific application needs. [ABSTRACT FROM AUTHOR]

High Ni‐layered oxides are promising cathode candidates for lithium‐ion batteries (LIBs) owing to their high‐specific capacity, high energy density, and low cost. However, their thermal and cycling performances often suffer from the inevitable interfacial reactions, oxygen loss, transition metal dissolution, and irreversible H2‐H3 lattice distortion. Herein, small doses of Zr/Y co‐doped and Al2O3 coated single‐crystal high‐Ni NCM (LiNi0.83Co0.12Mn0.05O2) materials (ZrY‐NCM@Al) are synthesized via a facile high‐temperature solid‐state reaction. The Al2O3 surface coating works as a protective layer to inhibit the side reaction on the interface between electrodes and electrolytes. The Zr/Y co‐doping improves the structural stability of the NCM and suppresses the irreversible structure transition from H2 to H3. When ZrY‐NCM@Al is used as a cathode, the square‐aluminum‐shell full battery with artificial graphite anode exhibits a high capacity of 50 Ah and a high energy density of 230 Wh kg−1. After 1000 cycles at 45 °C and 1 C constant current and constant voltage (CCCV), the battery retained 89.2% of its capacity and an energy density of 204 Wh kg−1, demonstrating excellent thermal and cycling performances. This study paves a novel route to the fabrication of high‐Ni cathode materials for LIBs with excellent cycling and thermal stability. [ABSTRACT FROM AUTHOR]

The deblurring of flotation froth images significantly aids in the characterization of coal flotation and fault diagnosis. Images of froth acquired at a flotation site contain considerable noise and blurring, making feature extraction and segmentation processing difficult. We present an effective method for deblurring froth images based on disentangled representations. Disentangled representation is achieved by separating the content and blur features in the blurred image using a content encoder and a blur encoder. Then, the separated feature vectors are embedded into a deblurring framework to deblur the froth image. The experimental results show that this method achieves a superior deblurring effect on froth images under various conditions, which lays the foundation for the intelligent adjustment of parameters to guide the flotation site. [ABSTRACT FROM AUTHOR]

MXenes as an emerging two‐dimensional (2D) material have attracted tremendous interest in electrochemical energy‐storage systems such as supercapacitors. Nevertheless, 2D MXene flakes intrinsically tend to lie flat on the substrate when self‐assembling as electrodes, leading to the highly tortuous ion pathways orthogonal to the current collector and hindering ion accessibility. Herein, a facile strategy toward multi‐scale structural engineering is proposed to fabricate high‐performance MXene hydrogel supercapacitor electrodes. By unidirectional freezing of the MXene slurry followed by a designed thawing process in the sulfuric acid electrolyte, the hydrogel electrode is endowed with a three‐dimensional (3D) open macrostructure impregnated with sufficient electrolyte and H+‐intercalated microstructure, which provide abundant active sites for ion storage. Meanwhile, the ordered channels bring through‐electrode ion and electron transportation pathways that facilitate electrolyte infiltration and mass exchange between electrolyte and electrode. Furthermore, this strategy can also be extended to the fabrication of a 3D‐printed all‐MXene micro‐supercapacitor (MSC), delivering an ultrahigh areal capacitance of 2.0 F cm–2 at 1.2 mA cm–2 and retaining 1.2 F cm–2 at 60 mA cm–2 together with record‐high energy density (0.1 mWh cm–2 at 0.38 mW cm–2). [ABSTRACT FROM AUTHOR]

MXene, as a new member of the two‐dimensional (2D) material family, has been widely studied. However, people often pay close attention to the versatility of MXene while ignoring its low exfoliation yield. In this work, a simplified and effective strategy to exfoliate multilayer‐MXene via the gentle water freezing‐and‐thawing (FAT) approach is proposed. The volume expansion of intercalated water can promote the exfoliation of MXene nanosheets. The yield of large FAT‐MXene flakes with special wrinkles can reach 39% after four cycles of the FAT process. Moreover, combining with sonication treatment can boost the yield of small MXene to a record high value of 81.4%. With the help of a commercial interdigital mask, an on‐chip all‐MXene micro‐supercapacitor (MSC) assembled by large FAT‐MXene is fabricated, exhibiting high areal and volumetric capacitance of 23.6 mF cm−2 and 591 F cm−3, respectively. This remarkable electrochemical performance of MXene‐MSC also confirms the high quality of MXene through this FAT strategy. This study may open up a new method to simultaneously boost the yield of MXene with small or large flake sizes, facilitating large‐scale and size‐dependent research on MXene. [ABSTRACT FROM AUTHOR]

Compton scattering can be used to determine the electron densities of tissues for medical applications and those of materials for industrial applications. Much work has been devoted to solving the reconstruction problem. Hussein proposed a successive approximation process (SAP) for the reconstruction of the density image from the Compton scattered energy spectral data [IEEE Trans. Nucl. Sci., 42, 2155 (1995)]. This algorithm is adapted directly from the neutron scattering tomography reconstruction where a convergence condition for such an algorithm was presented [Hussein and Meneley, Int. J. Multiphase Flow, 12, 1 (1986)]. However, we found that this condition is not correct in general cases and we cannot obtain such a simple form of convergence condition in terms of the maximum length(in unit of mean-free path) a neutron or a photon travels in any pixel in the test section. A detailed discussion of the convergence problem of SAP will be presented in this paper. [ABSTRACT FROM AUTHOR]