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The nanofiltration (NF) membrane has not been extensively competent for rejection of monovalent ions (such as Cl− and NO3−), and the strategy for enhancing monovalent ion rejection and permeation flux still faces a significant challenge. Herein, based on our previous polyethersulfone (PES)‐type NF membrane (NF‐0), two novel NF membranes were fabricated with additional incorporations of 2,2′‐benzidinedisulfonic acid (BDSA) and forward osmotic extraction solution‐functioned nanoparticles (MNPs) to remove nitrate from the aqueous solution. The fabricated NF‐BDSA membrane with introduction of BDSA in ultrathin layer displays a significant nitrate rejection of 92.2% and an acceptable permeation flux of 21 L m−1 h−1 at 0.6 MPa. As anticipated, the obtained NF‐MNPs1.0 membrane with additional incorporation of MNPs (1.0 wt% addition) in the substrate layer of NF‐BDSA membrane achieves further improvements in nitrate rejection (95%) and water permeability (32.3 L m−1 h−1); encouragingly, this membrane exhibits comparable monovalent ion rejection and permeation flux to reverse osmosis membrane under relatively low pressure. Compared with those of NF‐0 membrane, the permeation flux and nitrate rejection of NF‐MNPs1.0 membrane increase by 111.1% and 6.1%, respectively. Moreover, the superior performances of endurance, antifouling and chlorine resistance of NF‐MNPs1.0 membrane demonstrate its expectable perspective of potential engineering applications. [ABSTRACT FROM AUTHOR]

The anomalous Hall effect (AHE) that associated with the Berry curvature of occupied electronic states in momentum‐space is one of the intriguing aspects in condensed matter physics, and provides an alternative for potential applications in topological electronics. Previous experiments reported the tunable Berry curvature and the resulting magnetization switching process in the AHE based on strain engineering or chemical doping. However, the AHE modulation by these strategies are usually irreversible, making it difficult to realize switchable control of the AHE and the resultant spintronic applications. Here, we demonstrated the switchable control of the Berry‐curvature‐related AHE by electrical gating in itinerant ferromagnetic Cr7Te8 with excellent ambient stability. The gate‐tunable sign reversal of the AHE can be attributed to the redistribution of the Berry curvature in the band structure of Cr7Te8 due to the intercalation‐induced change in the Fermi level. Our work facilitates the applications of magnetic switchable devices based on gate‐tunable Berry curvature. [ABSTRACT FROM AUTHOR]

The nanofiltration (NF) membrane technology has attracted considerable attention for the rejection removal of various salts. However, the practical application of this membrane separation process has been severely retarded due to the ineffective rejection of monovalent ions (such as nitrate and chloride), undesirable filtration flux, and insufficient disposal of the concentrated solution. In this work, three polyethersulfone‐type NF membranes were fabricated and their morphologies, functional groups, chemical components, wettabilities, chargeabilities, and rejection molecular weights were characterized. Among them, the membrane of NF_M3 bearing sulfonic acid group (SO3H) shows the desirable rejection efficiency of nitrate (90.32%), acceptable solution filtration flux (10.15 L m−2 h−1 at 0.6 MPa), and the decent pure water permeation flux (50.8 L m−2 h−1 at 0.6 MPa). The introduction of SO3H can significantly enhance the performances of NF_M3 membrane in hydrophilicity, chargeability, anti‐fouling, and the oxidation resistance. Promisingly, the concentrated nitrate was ingeniously recycled for the electrochemical intercalation of flake graphite to prepare expandable graphite, and the obtained expanded graphite has an acceptable expanded volume (243 mL g−1 via the microwave expansion process), thereby achieving the resource utilization of NF concentrated solution. [ABSTRACT FROM AUTHOR]

Dielectric microspheres naturally possess unique optical properties by which the light's focus and confinement can be manipulated on a microscale. Combining microspheres and optical or Raman microscopy, super‐resolution imaging beyond the diffraction limit and enhancement of Raman signals are demonstrated to provide abundant spectroscopic information on materials. However, microsphere‐aided super‐resolution scanning photocurrent imaging remains challenging to date. Here, based on the photonic nanojet mechanism, a super‐resolution photocurrent and spectral microscopy equipped with a scanning tip with silica dielectric microspheres are presented. With such microsphere‐aided microscopy, order of magnitude enhancements for single‐point Raman and photoluminescence signals can be achieved, and the spatial resolutions for photocurrent and spectral mapping surpass the best resolution of the original confocal system restricted by the diffraction limit. This versatile system enables correlative super‐resolution spectral and photocurrent imaging, serving as a reliable tool for comprehensively understanding and uncovering the optoelectronic properties of materials. [ABSTRACT FROM AUTHOR]

In this paper, low‐strength polyvinyl alcohol (L‐PVA) fibers, high‐strength polyvinyl alcohol (H‐PVA) fibers, and polyethylene (PE) fibers were used to prepare ambient cured fly ash‐slag‐based engineered geopolymer composites (EGC). The effects of fiber types and fiber volume fractions (1.5%, 1.75%, 2.0%, 2.25%, and 2.5%) on the compressive strength and tensile performance of EGC were evaluated. It was found that by increasing the fiber volume fraction from 1.5% to 2.5%, L‐PVA fibers had the lowest influence, whereas PE fibers had the highest influence on the compressive strength of EGC. The optimum fiber volume fractions of L‐PVA, H‐PVA, and PE fibers were 1.75%, 2.25%, and 1.5%, respectively, for EGC to achieve the best tensile performance. Scanning electron microscope (SEM) investigations showed that the bonding performance of PE fibers to the EGC matrix was higher than those of L‐PVA and H‐PVA fibers to the EGC matrix. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junctions (MTJs), a prominent type of spintronic device based on the spin valve effect, have facilitated the development of numerous spintronic applications. The technical appeal for the next‐generation MTJ devices has been proposed in two directions: improving device performance by utilizing advanced two‐dimensional (2D) ferromagnetic materials or extending device functionalities by exploring the gate‐tunable magnetic properties of ferromagnets. Based on the recent development of 2D magnets with the ease of external stimuli, such as electric field, due to their reduced dimensions, reliable prospects for gate‐tunable MTJ devices can be achieved, shedding light on the great potential of next‐generation MTJs with multiple functionalities for various application environments. While the electrical gate‐tunable MTJ device is highly desirable for practical spintronic devices, it has not yet been demonstrated. Here, we demonstrate the experimental realization of a spin valve device by combining a vertical Fe3GeTe2/h‐BN/Fe3GeTe2 MTJ with an electrolyte gate. The magnetoresistance ratio (MR ratio) of 36% for the intrinsic MTJ confirms the good performance of the device. By electrolyte gating, the tunneling MR ratio of Fe3GeTe2/h‐BN/Fe3GeTe2 MTJ can be elevated 2.5 times, from 26% to 65%. Importantly, the magnetic fields at which the magnetoresistance switches for the MTJ can be modulated by electrical gating, providing a promising method to control the magnetization configuration of the MTJ. Our work demonstrates a gate‐tunable MTJ device toward the possibility for gate‐controlled spintronic devices, paving the way for performing 2D magnetism manipulations and exploring innovative spintronic applications. [ABSTRACT FROM AUTHOR]