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This study introduces a novel approach for generating highly effective CO2 adsorbents derived from glycated chitosan (GC) and electrochemically exfoliated graphene (EEG) nanoplatelets. The significant enhancement in the CO2 adsorption capacity of EEG-GC aerogels in comparison to their building blocks is achieved by inducing mesoporosity enabled by linking amine groups on GC and phosphate groups on EEG. The glycation of chitosan facilitates its enhanced dispersion in water, and effectively eliminates its amorphous parts, leading to a bimodal particle size distribution. The extent of glycation and the weight ratio of EEG to GC affect the precursor gel's microstructure and mesoporosity in the derived aerogels, with optimal conditions identified. The derived aerogels demonstrate exceptional CO2 adsorption capacity of 2.88 mmol g-1 and CO2/N2 selectivity of 43.8, at 298 K and 1 bar, and can be regenerated employing Joule heating with minimal reduction in adsorption capacity (demonstrated for 20 cycles). These findings highlight the innovative use of amine-phosphate coupling along with the bimodal distribution of GC to induce mesoporosity, providing new avenues for developing effective CO2 adsorbents for industrial use. [ABSTRACT FROM AUTHOR]

The urgent need for sustainable and efficient ammonia production has driven intense research towards alternative electrochemical routes. In this study, we present a comprehensive approach that leverages the properties of electrochemically exfoliated nitrogen-doped graphene (NG) combined with titanium nitride (TiN) and metal nanoparticles (NPs) for enhanced electrocatalytic nitrogen reduction reaction (NRR) under mild conditions. The TiN-modified NG nanohybrid demonstrates remarkable light absorption capabilities and a significantly expanded electrochemically active graphene surface, setting the stage for efficient NRR. Further optimization of the NRR is achieved by integrating platinum and ruthenium metal NPs into the TiN/NG structure, forming a PtRu@TiN/NG nanocomposite. Under light exposure, this nanocomposite exhibits an outstanding NH3 productivity of 316 μg h−1 mgcat−1 with a notable 64% faradaic efficiency, surpassing the dark reaction at −1 V which yields 207 μg h−1 mgcat−1. The substitution of N2 with Ar completely halts NH3 generation, emphasizing the essential role of N2 in the NRR process. The exceptional catalytic performance is attributed to the synergistic interplay of Pt–Ru alloying, TiN, and the monolayer of NG, facilitated by their intimate and extensive interfacial contact. While the current yields may not fully meet practical application requirements, this research presents a promising route for ambient NH3 production, emphasizing the potential for further advancements in active materials and reaction design to enhance ammonia synthesis. [ABSTRACT FROM AUTHOR]

The development of electrodes with high performance and long‐term stability is crucial for commercial application of vanadium redox flow batteries (VRFBs). This study compared the performance of VRFB with thermal‐treated and MXene‐modified carbon paper. To prepare the MXene, a modified‐etching process with ammonium−bifluoride (NH4HF2) led to a mild and efficient conversion of the MAX‐phase to MXene compared to etching process with hydrofluoric‐acid (HF). Electron microscopy and X‐ray diffraction studies revealed that the etching process with NH4HF2 led to MXene nanostructures with a large interlayer spacing. The results show that at a current density of 60 mA cm−2, the energy efficiency increased by 25.5 % when using a NH4HF2 ‐etched MXene‐modified negative electrode, by 12.5 % with a thermal‐treated MXene‐modified electrode, and by 4 % with an HF‐etched MXene‐modified electrode, in comparison to the pristine electrode. The maximum power density of the battery was increased by more than 40 %. In long‐term cycling experiments the MXene modified electrode exhibited excellent stability over 1000 cycles of charge‐discharge, with 0.05 % discharge capacity decay per cycle, amongst the lowest values reported to date and four times lower than for thermally‐treated electrode. The superior performance was linked to the improved electrical conductivity and wettability, higher interlayer spacing, and lower charge transfer resistance for the V2+/V3+ redox reaction. [ABSTRACT FROM AUTHOR]

Bivalve filter feeders, such as oysters, filter large volumes of water and are particularly exposed to microplastics (MP). Consequently, these animals digest and assimilate high levels of MP in their bodies that may likely impact their physiology, and potentially affect shellfish stocks, benthic habitats and, indirectly, the health status of the marine ecosystem and human consumers. In this study we exposed juvenile oysters, Crassostrea gigas, to 3 different MP concentrations (104, 105 and 106 particles L−1), represented by 6μm Polystyrene (PS) microbeads, compared to a control treatment receiving no MP. The study ran for a period of 80 days to test for the impacts of MP on growth, Condition Index and Lysosomal Stability. From histological analysis, microbeads were detected in the intestines of exposed oysters and in the digestive tubules, but no cellular inflammatory features were observed over time. Weight and shell length remained comparable between the different treatments and control. We found that Condition Index in the highest concentration increased initially but significantly reduced over time. The oysters in the highest MP exposure also showed the lowest mean Lysosomal Stability score throughout the experiment. Lysosomes play a vital role in the cells defense mechanisms and breakdown of constituents, crucial for the oysters’ wellbeing. Most importantly, we detected an increased mortality in those oysters who were chronically exposed to the highest loads of MP.

Due to intensive integration and seamless continuous operation, the overheated artificially intelligent (AI) integrated circuit systems will affect the operation system's effectiveness, stability, and lifetime. Therefore, we proposed a temperature adaptability memristor in the silver nanowires (AgNWs)/nanocomposite/indium–tin-oxide structure in this study. The nanocomposite is the nitrogen-doped graphene/Ti3CNTx MXene blend in the polyvinylidene fluoride matrix. The device has been prepared by using heterostructure nanocomposites with a low-cost and facile all-solution method. The device mimicked a series of trained behaviors inherent with biological synapses, including spike-timing-dependent plasticity, paired-pulse facilitation, short-term potentiation/depression, long-term potentiation/depression, and excitatory postsynaptic currents. In addition, the device demonstrated significant self-adaptability to temperature due to the involvement of the homogeneously distributed conductive heterostructure and the filament formation ascribed to the low melting point of AgNWs. The operation of the device shows temperature adaptability owing to the excellent thermal conductivity and small thermal expansion coefficient of nitrogen-doped graphene/Ti3CNTx. This finding provides viable strategies to address the critical challenges of deploying AI in different environments, paving the way for the development of more efficient and resilient neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

Aberrant expansion of KRT5+ basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic pulmonary fibrosis (IPF). The mechanisms determining activity of KRT5+ cells in IPF have not been delineated. Here, we reveal a potential mechanism by which KRT5+ cells migrate within the fibrotic lung, navigating regional differences in collagen topography. In vitro, KRT5+ cell migratory characteristics and expression of remodelling genes are modulated by extracellular matrix (ECM) composition and organisation. Mass spectrometry- based proteomics revealed compositional differences in ECM components secreted by primary human lung fibroblasts (HLF) from IPF patients compared to controls. Over-expression of ECM glycoprotein, Secreted Protein Acidic and Cysteine Rich (SPARC) in the IPF HLF matrix restricts KRT5+ cell migration in vitro. Together, our findings demonstrate how changes to the ECM in IPF directly influence KRT5+ cell behaviour and function contributing to remodelling events in the fibrotic niche. Idiopathic pulmonary fibrosis has been associated with aberrant expansion of KRT5-expressing basal cells. Here the authors show how changes in the ECM glycoprotein SPARC restrict the movement of KRT5+ cells, affecting their retention within fibrotic tissue. [ABSTRACT FROM AUTHOR]