Publications by authors named "Junyi Ji"

Single-atom catalysts (SACs) have attracted considerable interest in the field of electrocatalysis due to their high efficiency of metal utilization and catalytic activity. However, traditional methods of SACs fabrication are often complex and time-consuming. Herein, F-Ru@TiO N was synthesized using a straightforward and universal approach surface etching and heteroatoms immobilization on a vacancies-rich hierarchical TiO N nanorods array.

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Traditional ferroelectrics are limited by Neumann's principle, which confines exploration of ferroelectrics within polar point groups. Our recent work [Ji et al., Nat.

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The hydrogen evolution reaction (HER) holds great potential for sustainable hydrogen production but developing efficient and cost-effective electrocatalysts remains challenging. Here, we report the synthesis of a hierarchical WC/NiCoW hollow nanotube array electrocatalyst, featuring rapid gas release to minimize bubble aggregation and reaction retardation. Mechanistic insights into the HER kinetics reveal enhanced electron transfer at the WC-NiCoW interface and an accelerated Volmer step.

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Dynamic wireless power transfer (DWPT) systems with segmented transmitters suffer from output pulsations during the moving process. Although numerous coil structures have been developed to mitigate this fluctuation, the parameter design process is complicated and restricted by specific working conditions (e.g.

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Alkaline methanol-water electrolysis system is regarded as an appealing strategy for electro-reforming methanol into formate and producing hydrogen with low energy-consumption compared with alkaline water electrolysis. However, stability and selectivity under high current densities for practical application remain challenging. Herein, a CeF@NiN nanosheets array anchored on carbon cloth (CeF@NiN/CC) was fabricated.

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The stability of aqueous zinc metal anodes is still constrained by their severe dendrite growth. Optimizing electric field distribution and crystallography to modulate the diffusion and deposition behavior of zinc ions can effectively suppress dendrite growth. However, the fabrication strategy to directly endow specific textured zinc anodes with gradient electric field distribution is still lacking.

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The scarcity of fresh water necessitates sustainable and efficient water desalination strategies. Solar-driven steam generation (SSG), which employs solar energy for water evaporation, has emerged as a promising approach. Graphene oxide (GO)-based membranes possess advantages like capillary action and Marangoni effect, but their stacking defects and dead zones of flexible flakes hinders efficient water transportation, thus the evaporation rate lag behind unobstructed-porous 3D evaporators.

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For an ordinary ferroelectric, the magnitude of the spontaneous electric polarization is at least one order of magnitude smaller than that resulting from the ionic displacement of the lattice vectors, and the direction of the spontaneous electric polarization is determined by the point group of the ferroelectric. Here, we introduce a new class of ferroelectricity termed Fractional Quantum Ferroelectricity. Unlike ordinary ferroelectrics, the polarization of Fractional Quantum Ferroelectricity arises from substantial atomic displacements that are comparable to lattice constants.

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Design of admirable conductive hydrogels combining robust toughness, soft flexibility, desirable conductivity, and freezing resistance remains daunting challenges for meeting the customized and critical demands of flexible and wearable electronics. Herein, a promising and facile strategy to prepare hydrogels tailored to these anticipated demands is proposed, which is prepared in one step by homogeneous cross-linking of acrylamide using hydrophobic divinylbenzene stabilized by micelles under saturated high-saline solutions. The influence of high-saline environments on the hydrogel topology and mechanical performance is investigated.

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Solar-driven interfacial evaporation (SIE) technology has great advantages in seawater desalination. However, during the long-term operation of a solar evaporator, salts can be deposited on the solar absorbing surface, which, in turn, hinders the evaporation process. Therefore, there is an urgent need to propose new antisalt strategies to solve this problem.

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Developing cost-effective Pt-based electrocatalysts for the hydrogen evolution reaction (HER) is highly urgent. Herein, we report novel electrocatalysts with individually dispersed Pt active sites and tunable Pt-Ni interaction decorated on carbon-wrapped nanotube frameworks (Pt/Ni-DA). Pt/Ni-DA exhibits superior HER performance at low Pt concentrations with an ultralow overpotential of 18 mV at 10 mA cm and an ultrahigh mass activity of 2.

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Article Synopsis
  • High sugar diets in high-income countries may negatively impact the function of intestinal stem cells (ISCs) and transit-amplifying (TA) cells, which are crucial for maintaining the colonic epithelium and repairing damage.
  • Research using colonoids and a mouse model showed that excess sugar limits the development and proliferation of these cells by reducing the expression of growth-related genes and altering their metabolic pathways.
  • Findings suggest that short-term high-sucrose intake can inhibit the regenerative capabilities of ISCs and TA cells, potentially guiding dietary choices for better recovery from intestinal injuries.
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Article Synopsis
  • - The study focuses on improving self-standing graphene membranes for use as electrodes in supercapacitors, which have challenges in maintaining uniformity and performance.
  • - A novel method combines metal cation chelation and high-speed spinning to create uniform interlayer channels in graphene oxide membranes, significantly enhancing their electrochemical properties.
  • - The resulting iron cross-linked graphene oxide membranes show impressive performance metrics, including a high specific capacitance of 427 F g and excellent longevity after 20,000 cycles, indicating great potential for applications in energy storage and other fields.
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Two-dimensional (2D) ferroelectrics, which are rare in nature, enable high-density nonvolatile memory with low energy consumption. Here, we propose a theory of bilayer stacking ferroelectricity (BSF), in which two stacked layers of the same 2D material, with different rotation and translation, exhibit ferroelectricity. By performing systematic group theory analysis, we find all the possible BSF in all 80 layer groups (LGs) and discover the rules about the creation and annihilation of symmetries in the bilayer.

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Small-caliber tissue-engineered vascular grafts (TEVGs, luminal diameter <6 mm) are promising therapies for coronary or peripheral artery bypassing surgeries or emergency treatments of vascular trauma, and a robust seed cell source is required for scalable manufacturing of small-caliber TEVGs with robust mechanical strength and bioactive endothelium in future. Human-induced pluripotent stem cells (hiPSCs) could serve as a robust cell source to derive functional vascular seed cells and potentially lead to generation of immunocompatible engineered vascular tissues. Up to date, this rising field of small-caliber hiPSC-derived TEVG (hiPSC-TEVG) research has received increasing attention and achieved significant progress.

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Oxygen vacancies occupation and coordination environment modulation of the transition-metal based electrodes are effective strategies to improve the structural stability and electrochemical performance. In this work, the 2-methylimidazole (2-MI) doped manganese dioxide (MnO) anchored on carbon cloth (CC) is fabricated via a simple method (MI-MnO/CC), where the oxygen defects on/inside the K doped δ-MnO nanosheets are in-situ created by reductive ethanol/Mn and occupied by 2-MI ligands. With the pre-embedded K ions and abundant ligand-refilled defects, the electronic coordination structure, structural stability and electron/ion diffusion efficiency can be effectively enhanced.

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Organic-inorganic multiferroics are promising for the next generation of electronic devices. To date, dozens of organic-inorganic multiferroics have been reported; however, most of them show a magnetic Curie temperature much lower than room temperature, which drastically hampers their application. Here, by performing first-principles calculations and building effective model Hamiltonians, we reveal a molecular orbital-mediated magnetic coupling mechanism in two-dimensional Cr(pyz) (pyz = pyrazine) and the role that the valence state of the molecule plays in determining the magnetic coupling type between metal ions.

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Tailoring the porous structure of carbon materials is one essential approach to improve the energy storage performance of carbon-based electrode materials. Herein, hierarchical porous carbons (HPCs) with different meso-structure are synthesized via a one-pot pyrolysis process with SiO and ZnCl as template and activator, respectively. The energy storage capacities of the obtained HPC samples are investigated as bi-functional electrode both for supercapacitor and LIBs.

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Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment; however, immune-related adverse events (irAEs) in the gastrointestinal (GI) system commonly occur. In this study, data were obtained from the US Food and Drug Administration adverse event reporting system between July 2014 and December 2020. Colitis, hepatobiliary disorders, and pancreatitis were identified as irAEs in our study.

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Developing highly active water splitting electrocatalysts with ordered micro/nanostructures and uniformly distributed active sites can meet the increasing requirement for sustainable energy storage/utilization technologies. However, the stability of complicated structures and active sites during a long-term process is also a challenge. Herein, we fabricate a novel approach to create sufficient atomic defects via N plasma treatment onto parallel aligned NiMoO nanosheets, followed by refilling of these defects via heterocation dopants and stabilizing them by annealing.

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Patients with inflammatory bowel disease, psoriasis or other rheumatic diseases treated with corticosteroids, immunomodulators and biologics might face additional risk during COVID-19 epidemic due to their immunocompromised status. However, there was still no unanimous opinion on the use of these therapy during COVID-19 epidemic. Current studies suggested that systemic corticosteroids might increase the risk of hospitalization, as well as risks of ventilation, ICU, and death among patients with immune-mediated inflammatory diseases.

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Based on their characteristics, transition metal layered double hydroxides have been of great scientific interest for their use in supercapacitors. Up until now, severe aggregation and low intrinsic conductivity have been the major hurdles for their application. In this work, nickel-iron sulfide nanosheets (NiFeSx) and carbon nanotubes (CNTs) were synthesized on diatomite using chemical vapor deposition and a two-step hydrothermal method to overcome these challenges.

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Ionic species are important to dominate phase separation behaviors of poly(N-isopropylacrylamide) (PNIPAm) in aqueous solutions. Herein, photoresponsive azobenzene-based salts with various ions are prepared and their photoresponsive ion effects on clouding temperatures (T ) of PNIPAm in aqueous solutions are explored. It is found that, despite of various structures of anions and cations, trans-T under vis light irradiation are always higher than cis-T under UV irradiation.

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Graphene oxide (GO) membranes have shown enormous promise in desalination and molecular/ionic sieving. However, the instability of GO membranes in aqueous solutions seriously hinders their practical applications. Herein, we report a novel and simple strategy to fabricate stable GO membranes in water-based environments through the insertion of various metal cations from metal foils (.

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