Sintering protonic zirconate cells with enhanced electrolysis stability and Faradaic efficiency
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Urine electrooxidation for energy–saving hydrogen generation
Urea electrooxidation offers a cost-effective alternative to water oxidation for energy-saving hydrogen production. However, its practical application is limited by expensive urea reactants and sluggish reaction kinetics. Here, we present an efficient urine electrolysis system for hydrogen production, using cost-free urine as feedstock. Our system leverages a discovered Cl-mediated urea oxidation mechanism on Pt catalysts, where adsorbed Cl directly couple with urea to form N-chlorourea intermediates, which are then converted into N2 via intermolecular N–N coupling. This rapid mediated-oxidation process notably improves the activity and stability of urine electrolysis while avoiding Cl-induced corrosion, enabling over 200 hours of operation at reduced voltages. Accordingly, a notable reduction in the electricity consumption is achieved during urine electrolysis (4.05 kWh Nm−3) at 300 mA cm−2 in practical electrolyser for hydrogen production, outperforming the traditional urea (5.62 kWh Nm−3) and water (4.70–5.00 kWh Nm−3) electrolysis.
Distance-controlled direct ink writing of titanium alloy with enhanced shape diversity and controllable porosity
Porous titanium alloys have been extensively used for diverse engineering applications. However, current additive manufacturing (AM) strategies face significant challenges (e.g., low fabrication efficiency and limited shape diversity) in producing porous titanium alloys. This work aims to develop a distance-controlled direct ink writing (DC-DIW) approach for constructing macroscale 3D architectures from titanium alloy powders. This approach integrates a constant interlayer distance control with traditional DIW, breaking through the angle limit in current porous metal printing from 60° to 30°. Additionally, subsequent heat treatment is applied to control microstructures. To demonstrate the capabilities of this approach, three representative structures, including a bifurcated tube, an orbital implant, and a knee implant, are successfully printed and treated, achieving suitable mechanical properties and high shape fidelity. This work provides a viable and efficient AM strategy for fabricating porous titanium alloys with enhanced shape diversity and controllable porosity suitable for various engineering applications.
Type 2 immunity in allergic diseases
Significant advancements have been made in understanding the cellular and molecular mechanisms of type 2 immunity in allergic diseases such as asthma, allergic rhinitis, chronic rhinosinusitis, eosinophilic esophagitis (EoE), food and drug allergies, and atopic dermatitis (AD). Type 2 immunity has evolved to protect against parasitic diseases and toxins, plays a role in the expulsion of parasites and larvae from inner tissues to the lumen and outside the body, maintains microbe-rich skin and mucosal epithelial barriers and counterbalances the type 1 immune response and its destructive effects. During the development of a type 2 immune response, an innate immune response initiates starting from epithelial cells and innate lymphoid cells (ILCs), including dendritic cells and macrophages, and translates to adaptive T and B-cell immunity, particularly IgE antibody production. Eosinophils, mast cells and basophils have effects on effector functions. Cytokines from ILC2s and CD4+ helper type 2 (Th2) cells, CD8 + T cells, and NK-T cells, along with myeloid cells, including IL-4, IL-5, IL-9, and IL-13, initiate and sustain allergic inflammation via T cell cells, eosinophils, and ILC2s; promote IgE class switching; and open the epithelial barrier. Epithelial cell activation, alarmin release and barrier dysfunction are key in the development of not only allergic diseases but also many other systemic diseases. Recent biologics targeting the pathways and effector functions of IL4/IL13, IL-5, and IgE have shown promising results for almost all ages, although some patients with severe allergic diseases do not respond to these therapies, highlighting the unmet need for a more detailed and personalized approach.
Terminal differentiation and persistence of effector regulatory T cells essential for preventing intestinal inflammation
Regulatory T (Treg) cells are a specialized CD4+ T cell lineage with essential anti-inflammatory functions. Analysis of Treg cell adaptations to non-lymphoid tissues that enable their specialized immunosuppressive and tissue-supportive functions raises questions about the underlying mechanisms of these adaptations and whether they represent stable differentiation or reversible activation states. Here, we characterize distinct colonic effector Treg cell transcriptional programs. Attenuated T cell receptor (TCR) signaling and acquisition of substantial TCR-independent functionality seems to facilitate the terminal differentiation of a population of colonic effector Treg cells that are distinguished by stable expression of the immunomodulatory cytokine IL-10. Functional studies show that this subset of effector Treg cells, but not their expression of IL-10, is indispensable for colonic health. These findings identify core features of the terminal differentiation of effector Treg cells in non-lymphoid tissues and their function.
Tailoring the grain boundary structure and chemistry of the dendrite-free garnet solid electrolyte Li6.1Ga0.3La3Zr2O12
Garnet-type Li6.1Ga0.3La3Zr2O12 (LGLZO) exhibits high ionic conductivity and extremely low electronic conductivity. The electrochemical properties strongly depend on the characteristics of the grain boundaries and pores in the oxide–ceramic electrolyte. Currently, the main issue of LGLZO is its large grain boundary resistance due to high-temperature sintering. Herein, we propose an effective method for reinforcing the chemical and structural characteristics of the grain boundaries using a Li2O-B2O3-Al2O3 (LBA) sintering aid. In this study, the LBA sintering aid is critical because it fills grain boundaries and void spaces. As a result, LGLZO solid-state electrolytes with sintering aids significantly enhance the ionic conductivity and reduce the activation energy, especially in the grain boundary region. Another crucial issue is the formation of Li dendrites in LGLZO. Since dendritic Li propagates along the grain boundaries, the optimized LGLZO solid-state electrolyte demonstrates excellent stability against Li metals. Overall, the LGLZO electrolyte with the LBA sintering aid exhibits stable long-term cycling performance due to the well-designed grain boundaries.
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