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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]

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]

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]

Fine-tuning the interfacial sites within heterogeneous catalysts is pivotal for unravelling the intricate structure-property relationship and optimizing their catalytic performance. Herein, a simple and versatile mixed-dimensional assembly approach is proposed to create nanocrystal-on-nanowire superstructures with precisely adjustable numbers of biphasic interfaces. This method leverages an efficient self-assembly process in which colloidal nanocrystals spontaneously organize onto Ag nanowires, driven by the solvophobic effect. Importantly, varying the ratio of the two components during assembly allows for accurate control over both the quantity and contact perimeter of biphasic interfaces. As a proof-of-concept demonstration, a series of Au-on-Ag superstructures with varying numbers of Au/Ag interfaces are constructed and employed as electrocatalysts for electrochemical CO2-to-CO conversion. Experimental results reveal a logarithmic linear relationship between catalytic activity and the number of Au/Ag interfaces per unit mass of Au-on-Ag superstructures. This work presents a straightforward approach for precise interface engineering, paving the way for systematic exploration of interface-dependent catalytic behaviors in heterogeneous catalysts., (© 2024 Wiley‐VCH GmbH.)