化学最新文献

Layered double hydroxides (LDHs) are considered promising materials for supercapacitor applications. However, the development of yarn-shaped supercapacitors (YSCs) with high electrochemical performance utilizing LDHs remains challenging. In this study, the NiCo-LDHs with various morphologies (nano-needles, nano-sheets, needle-sheet composites, and nano-flowers) were grown on carbon nanotubes (CNTs)-functionalized cotton yarn via a co-precipitation technique for YSC applications. Among these, the yarn incorporating nano-needle NiCo-LDHs exhibited reduced crystallinity yet demonstrated a superior areal capacitance compared to other morphologies, following a diffusion-controlled process. Finite element simulations were subsequently conducted to investigate this phenomenon, revealing that the lower-crystallinity nano-needle NiCo-LDHs accumulated a greater charge at their tips, thereby enhancing redox reactions and achieving higher energy storage capacitance. Subsequently, the yarns with nano-needle NiCo-LDHs were assembled into flexible quasi-solid-state symmetric YSCs, achieving a peak areal capacitance of 124.27 mF cm^-2 and an exceptionally high energy density of 39.4 μWh cm^-2 at a current density of 0.2 mA cm^-2. Furthermore, our YSCs can be scaled up through serial or parallel connections and integrated into fabrics, making them suitable for wearable energy storage applications. This work provides an efficient method for fabricating high-performance YSCs and demonstrates significant potential for wearable energy storage devices.

The application of solid-state electrolytes (SSEs) is anticipated to enhance the safety performance of lithium metal batteries (LMBs). However, the progress of SSEs has been hindered by the unstable electrode-electrolyte interfaces (EEIs). In this study, in-situ polymerization of 1,3-dioxolane (DOL) is employed for the preparation of SSEs, with the addition of tributyl borate (TBB) to establish stable EEIs, particularly under high-voltage conditions. On one hand, the addition of TBB promotes the dissociation of lithium salts and increases the concentration of free Li⁺, resulting in an increase in room temperature ionic conductivity to 1.13 × 10^-4 S cm^-1 and an improvement in the Li⁺ transference number to 0.69 for the prepared poly-DOL electrolytes (PDE-TBB). Benefiting from the enhanced Li⁺ transport, the Li/PDE-TBB/Li symmetric cell exhibits a cycle life exceeding 1,000 h with a low polarization voltage as low as 12 mV, and the Li/PDE-TBB/LiFePO₄ cell demonstrates exceptional cyclic stability over 800 cycles at 1C, with a coulombic efficiency exceeding 99.8 % and a capacity retention of 89.6 %. On the other hand, PDE-TBB exhibits improved stability under high-voltage conditions and the capacity to establish robust boron-rich cathode electrolyte interphase (CEI) on the LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) surface, thereby enhancing the structural stability of cathode materials and ensuring exceptional cycling performance of Li/PDE-TBB/NCM811cell. This work presents a promising strategy for developing novel ether-based SSEs suitable for high-voltage lithium metal batteries.

The electrochemical performance of lithium metal batteries (LMBs) was hampered by the uncontrolled growth of lithium (Li) dendrites. To address this issue, the extensive application of artificial solid electrolyte interphase (SEI) coatings on anode surfaces emerged as an effective solution. Electrospinning, as an innovative technique for fabricating artificial SEI layers on the surface of copper (Cu) foil, effectively mitigated Li volume strain during cycling. In this study, an electrospun organic-inorganic composite nanofiber membrane was in-situ fabricated on Cu foil, serving as an artificial SEI layer (CuWs) for anode-free LMBs (AF-LMBs) to enhance battery performance. Lithiophilic polyvinylpyrrolidone was used as the polymer matrix, and Cu nitrate served as the inorganic functional particles capable of in-situ redox reactions. The CuWs with their three-dimensional (3D) network structure accommodated electrode volume changes and suppressed Li dendrite growth during Li deposition and stripping. Additionally, CuWs facilitated the in-situ generation of Li nitrate (LiNO₃), which helped stabilize SEI layer and enhance Li utilization. The release sites of LiNO₃ on the nanofibers enabled the in-situ reduction of metallic Cu, providing nucleation sites for Li deposition and forming the 3D ion-electron hybrid conductive networks. This CuWs layer reduced interfacial resistance and nucleation barriers, promoting uniform Li⁺ distribution on the anode surface. Li-Cu cells incorporating CuWs exhibited remarkable cycling stability, enduring over 460 cycles at 1.0 mA cm^-2 and 1.0 mAh cm^-2 with an average Coulombic efficiency of over 98.6 %. In Li-poor cells, the LFP|PE|CuWs achieved stable cycling for more than 30 cycles at 1.0 C, with a capacity retention rate of 92.0 %. These findings demonstrated that the CuWs membrane significantly enhanced the electrochemical performance of Li-poor cells and provided a novel artificial SEI protective strategy for advanced AF-LMBs with high energy density.

Compared with the complex components of raw biomass, biomass derivatives with defined structures are more conducive to the controllable synthesis of hard carbon (HC) materials. Starch-based HC has garnered significant attention because of its cost-effectiveness; however, its practical applicability is limited by poor thermal stability. Herein, we propose a strategy for improving the stability of starch through self-assembly crosslinking modification, yielding high-performance HC. Starch and citric acid form a dense crosslinked structure through esterification between hydroxyl and carboxyl groups, effectively overcoming the poor thermal stability. The resulting HC exhibits a low specific surface area (SSA) and abundant closed pore structures, thereby enabling substantial sodium-ion storage. The optimized HC exhibits an improved reversible capacity of 378 mAh g^-1 and an initial Coulombic efficiency (ICE) of 90.9 %. After 100 cycles at 0.5 C, it retains 98 % initial capacity. The assembled full-cell shows a high energy density of 248 Wh kg^-1. Furthermore, the structure-performance relationship analysis reveals that the slope capacity is primarily affected by the defect concentration, while the plateau capacity is mainly determined by the closed pore structure. Galvanostatic intermittent titration technique (GITT) tests and in-situ Raman spectroscopy reveal that the sodium-ion storage mechanism in starch-based HC is "adsorption-intercalation/filling."

Considering the desired energy density, safety and cost-effectiveness, rechargeable zinc-ion batteries (ZIBs) are regarded as one of the most promising energy storage units in next-generation energy systems. Nonetheless, the service life of the current ZIBs is significantly limited by rampant dendrite growth and severe parasitic reactions occurring on the anode side. To overcome these issues caused by poor interfacial ionic conduction and water erosion, we have developed a facile strategy to fabricate a uniform zinc borate layer at the zinc anode/electrolyte interface (ZnBO). Such protective layer integrates superhydrophobic-zincopholic properties, which can effectively eliminate the direct contact of water molecules on the anode, and homogenize the interfacial ionic transfer, thereby enhancing the cyclic stability of the zinc plating/stripping. As a result, the as-prepared ZnBO-coated anode exhibits extended lifespan of 1200 h at 1 mA cm^-2 and demonstrates remarkable durability of 570 h at 20 mA cm^-2 in Zn||Zn symmetric cells. Additionally, when coupled to an NH₄V₄O₁₀ (NVO) cathode, it also delivers a superior cyclability (203.5 mAh/g after 2000 cycles at 5 A/g, 89.3 % capacity retention) in coin full cells and a feasible capacity of 2.5 mAh at 1 A/g after 200 cycles in pouch full cells. This work offers a unique perspective on integrating hydrophobicity and zincophilicity at the anode/electrolyte interface through an artificial layer, thereby enhancing the cycle lifespan of ZIBs.

Covalent organic frameworks (COFs) have shown great potential in the photocatalytic production of hydrogen peroxide (H₂O₂) due to their precisely designed and customized ability. Nevertheless, the quest for efficient overall photosynthesis of H₂O₂ in pure water without sacrificial agents using COF photocatalysts remains a formidable challenge. Herein, three pyrene-based covalent organic frameworks are synthesized using an advanced interfacial design strategy. By incorporating functional groups of F, H, and OH into a COF skeleton, their wettability and charge-separation properties are fine-tuned. These COFs show great performances as photocatalysts for H₂O₂ production from water and air by utilizing both the oxygen reduction reaction and water oxidation reaction pathways. Compared to PyCOF-F and PyCOF-H, PyCOF-OH demonstrates superior H₂O₂ production efficiency due to its improved hydrophilicity and enhanced carrier separation, achieving a remarkable rate of 2961 µmol g^-1 h^-1 from 25 mL pure water and air. Further, the mechanism of H₂O₂ production over PyCOF-OH is clarified by combining a series of control experiments, in situ characterizations, and theoretical calculations. This study offers valuable insights into the interfacial design of high-performance photocatalysts for H₂O₂ synthesis.

Indoor air pollution, predominantly caused by volatile organic compounds (VOCs), poses significant health hazards when concentrations surpass critical thresholds. Using waste corn straw as carbon source and urea as nitrogen source, straw derived carbon aerogel (CAGH) loaded with g-C₃N_{4H2O-N2-450-3 h} was successfully prepared by hydrothermal and water-assisted calcination. Following water-assisted regulation, g-C₃N_{4H2O-N2-450-3 h} on CAGH exhibited a mixed structure comprising honeycomb and two-dimensional filaments, while the growth of g-C₃N_{4H2O-N2-450-3 h} was uniformly distributed on carbon aerogel in a line-surface combination fashion. This innovative binding method not only enhanced the loading capacity of g-C₃N₄ and the mechanical elasticity of aerogel, but also exposed a large number of adsorption sites, resulting in a significant increase in its adsorption capacity for VOCs, exceeding that of commercial activated carbon (AC). In comparison to pure g-C₃N₄, CAGH exhibited an expanded photo-response range. Under the exposure of visible light, CAGH proved highly effective in eliminating 73.87 % of toluene. In addition, it has demonstrated efficient removal of formaldehyde and acetone VOCs with good cyclic stability. Therefore, this work aims to reduce the emission of pollutants at source and provide an effective and economical strategy for the preparation of clean building materials from renewable materials, with potential applications in the environmental field.

Hydroxychloroquine sulfate (HCQ) is extensively utilized due to its numerous therapeutic effects. Because of its properties of high solubility, persistence, bioaccumulation, and biotoxicity, HCQ can potentially affect water bodies and human health. In this study, the LaCo_0.95Mo_0.05O₃-CeO₂ material was successfully prepared by the sol-gel process, and it was applied to the experiment of degrading HCQ by activating peroxymonosulfate (PMS). The results of characterization analysis showed that LaCo_0.95Mo_0.05O₃-CeO₂ material had good stability, and the problem of particle agglomeration had been solved to some extent. Compared with LaCo_0.95Mo_0.05O₃ material, it had a larger specific surface area and more oxygen vacancies, which was helpful to improve the catalytic activity for PMS. Under optimal conditions, the LaCo_0.95Mo_0.05O₃-CeO₂/PMS system degraded 95.5 % of HCQ in 10 min. The singlet oxygen, superoxide radicals, and sulfate radicals were the main radicals for HCQ degradation. The addition of Mo⁶⁺/Mo⁴⁺ and Ce⁴⁺/Ce³⁺ promoted the redox cycle of Co³⁺/Co²⁺ and enhanced the degradation rate of HCQ. Based on density functional theory and experimental analysis, three HCQ degradation pathways were proposed. The analysis of T.E.S.T software showed that the toxicity of HCQ was obviously reduced after degradation. The LaCo_0.95Mo_0.05O₃-CeO₂/PMS system displayed excellent reusability and the ability to remove pollutants in a wide range of real-world aqueous environments, with the ability to treat a wide range of pharmaceutical wastewater. In summary, this study provides some ideas for developing heterogeneous catalysts for advanced oxidation systems and provide an efficient, simple, and low-cost method for treating pharmaceutical wastewater that has good practical application potential.

Phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) is a low-abundance signaling lipid that plays crucial roles in various cellular processes, including endolysosomal system structure/function, stress response, and cell cycle regulation. PI(3,5)P2 synthesis increases in response to environmental stimuli, yet its behavior in cycling cells under basal conditions remains elusive. Here, we analyzed spatiotemporal changes in PI(3,5)P2 levels during the cell cycle of S. cerevisiae. We found that PI(3,5)P2 accumulates on the vacuole in the daughter cell while it disappears from the vacuole in the mother cell during mitosis. Concomitant with the changes in PI(3,5)P2 distribution, the daughter vacuole became more acidic, whereas the acidity of the mother vacuole decreased during mitosis. Our data further showed that both PI(3,5)P2 and the PI(3,5)P2 effector protein Atg18 are determinants of vacuolar-pH asymmetry and acidity. Our work, thus, identifies PI(3,5)P2 as a key factor for the establishment of vacuolar-pH asymmetry, providing insights into how the mother cell ages while the daughter cell is rejuvenated.

Some biomarkers of acute aortic dissection (AAD) can be used for the potential supplementary diagnosis of AAD, such as C-reactive protein (CRP), smooth muscle myosin heavy chain (SmMHC), and D-dimer (D-D). However, the current measurement methods for common markers primarily rely on sophisticated instruments. The operation process is complicated, and the reagents used are expensive. To provide chronic disease monitoring and home self-examination services for potential AAD patients in real time, we developed a smartphone-based multichannel magnetoelastic (ME) immunosensing device to detect protein levels. Our immunosensor reduced the aforementioned restrictions and demonstrated excellent performance for the supplementary diagnosis of AAD. In this paper, we successfully combined the intelligent terminal with the hardware system to sample the resonance frequency shift (RFS) on the multichannel ME immunosensor. According to the target detection objects with their respective antibodies in the immune binding response, multiple experiments were conducted to detect multiple groups of samples, and we found that a CRP concentration, a SmMHC concentration, and a D-D concentration in the range of 0.1-100μg/mL, 1-4ng/mL, and 0.25-5μg/mL were linearly proportional to the RFS of the ME immunosensor, respectively. For CRP, SmMHC, and D-D, the sensitivities were 13.37Hz/μg∙mL^-1, 155.19Hz/ng∙mL^-1, and 332.72Hz/μg∙mL^-1, respectively, and the detection limits were 2.634×10^-3μg/mL, 1.155×10^-2ng/mL, and 3.687×10^-3μg/mL, respectively. The experiments demonstrated that the accuracy and stability of our device were comparable to those of the vector network analyzer (VNA, Calibration instrument).