Betaine-modified La-doped ferrihydrite for efficient phosphate removal to ultralow levels.

Hydrogen bond-mediated surface microenvironment regulation of folic acid-functionalized carbon dots for pentoxifylline drug sensing.

How water models influence the interfacial organization of oxysterol epimers: A comparative simulation study using TIP3P and OPC.

Calcium ions as catalysts: Quantum chemical and experimental study of creatine cyclization to creatinine.

Surface charge modulated hydrogel for faster atmospheric water harvesting.

Self-sustaining humidity gradient in nanocellulose moist-electric transparent generator via hydrophilic-hydrophobic Janus interfaces.

Oral environment targeting sutures for refractory oral wound.

Tribridged hydroxyl groups regulated by Ni/La ratio for enhanced ozone decomposition over Ni-La bimetallic basic carbonate catalysts.

H+-empowered potassium vanadate cathode: An electron/ion/interface trifecta for high-performance zinc-ion batteries.

Aging dynamics of bulk nanobubbles under pressure oscillations.

Conformations of polyglutamate chains near single walled carbon nanotubes.

The important task of medical materials science is to create multifunctional materials, particularly, materials for bone replacement with improved adsorption properties to load them with drugs for their direct local action in an area of the lesion. In this regard, the aim of work is to study the kinetics of adsorption-desorption of water vapor on biogenic hydroxyapatite/glass/carbon fiber (BHA/glass/CF) composites depending on the content of the fiber component, as well as to study their specific surface area, morphology, and thermal stability. The study allows for the prediction of the behavior of composites during their storage and further use as medical materials. Microstructural studies were performed by scanning electron microscopy (SEM). The specific surface area of the materials was determined by gas adsorption (Brunauer-Emmett-Teller theory, BET). The kinetics of adsorption and desorption of water vapor were studied using the gravimetric method of analysis. Thermal analysis (TG-DTA) was performed in air within a temperature range from 20 to 1000 °C. The TG-DTA method of the starting materials and the obtained composites confirmed that the technology used for their preparation allows for keeping carbon fibers in the structure. The SEM studies demonstrated a complex specific porous structure of the obtained BGA/glass/СF biocomposites with the presence of visible carbon fibers in their structure. It has been found that the specific surface area of the composites can be varied from 101 to 537 m2/g by changing the carbon fiber content from 10 to 50 %. It has been shown that biocomposites’ adsorption properties also depend on the carbon fibers’ content. According to a 24-hour study of the adsorption process, it was found that the value of the reduced adsorbed mass of water molecules increases from 0.0392 to 0.162 with an increase in the carbon fiber content from 10 to 50 %. It was shown that the desorption process is a linear function of temperature and depends on an increase in the rate of temperature increase.

The combination band just above 2000 cm-1 appearing in the infrared spectrum of liquid water is well known from experiments, and it is thought to originate from the combination of bending motions of the water molecules and the large-amplitude libration modes of the condensed phase. While classical simulations cannot genuinely reproduce this band, here we show that this exquisitely quantum signal can be simulated by on-the-fly abinitio semiclassical molecular dynamics. The number of atoms involved in reproducing this combination band, which is also known as the "association band" of liquid water, shows that this condensed phase signal is quite local.

The Chikungunya virus (CHIKV), transmitted by Aedes mosquitoes, initiates infection through direct engagement with MXRA8, a host receptor for arthritogenic alphaviruses. In this work, classical molecular dynamics simulations combined with qauantum descriptors of bonding interactions, including non-covalent interaction (NCI) plots, quantum theory of atoms in molecules (QTAIM), and natural bond orbital (NBO) calculations, are used to elucidate the nature and strength of the intermolecular interactions driving CHIKV recognition and attachment. We provide evidence to show that regardless of initial conditions, force fields, and software, the virus and receptor form a stable complex where the most prevalent interactions are due to arginine-aspartate contacts, but also come from the cooperative action of a large number of individually weak contacts, yielding an extended region of non-covalent direct protein protein, solvent-mediated protein protein, and glycan protein interactions. Based on quantum chemical calculations, we show that a good part of the stabilization of the CHIKV· · ·MXRA8 complex arises from the energetic contributions given by eight persistent direct protein protein and the electron transfer from water molecules to the protein protein interstitial region. These findings highlight the intrinsic complexity of the CHIKV MXRA8 recognition and attachment process in the context of the identified hot spots for protein protein interactions. While the persistent interstitial interactions that play relevant roles can be well characterized, their stability and specificity are reinforced by a surrounding cooperative network of non-covalent contacts, including solvent mediated interactions and contributions from neighboring residues and glycans. Together, this dynamic and interconnected interaction network governs viral attachment and stabilizes the protein protein binding interface.

Humidity exerts a profound influence on human life, making the monitoring of atmospheric humidity critically important. To address the growing demand for low-power, lightweight, and environmentally friendly humidity sensors, increasing research efforts are focused on the development of self-powered humidity sensors. Self-powered humidity sensors based on the moist-electric effect can directly generate electrical signals through the adsorption and desorption behavior of water molecules in the air, without requiring external mechanical contact. However, current humidity sensors based on the moist-electric effect suffer from issues such as weak electrical output and an inability to produce sustained electrical output, limiting their practical application. This study uniformly disperses a covalent organic framework (COF) and cellulose nanofibers (CNF) to form a novel humidity-sensitive hybrid aerogel. Using the COF/CNF aerogel as a substrate, a humidity sensor operating via the moist-electric effect was fabricated. This sensor can be used for monitoring human respiration under different states and for noncontact sensing of finger movements. COF exhibits high hydrolytic stability and abundant polar functional groups. When combined with CNF, it forms synergistic effects, offering advantages of uniform dispersion and enhanced moisture absorption. This not only enables the device to achieve exceptional humidity response linearity across its sensing range (R2 = 0.991), but also significantly enhances the device's electrical output intensity, achieving a high open-circuit voltage of 0.84 V and a sensitivity reaching 14 mV/% RH. The TMEG-based humidity sensor maintains a stable voltage output of 0.55-0.6 V for at least 5 h under environmental humidity conditions. Benefiting from its high output and robust output stability, this aerogel platform provides a practical route toward self-powered humidity sensing for potential environmental monitoring and low-power sensing.

Additive engineering in aqueous zinc-ion batteries is recognized as a key strategy for improving zinc anode stability. Nevertheless, the conventional trial-and-error screening approach is inefficient, which significantly hinders commercialization progress. This work proposes a descriptor framework-driven strategy integrating machine learning with dual validation from simulations and experiments to enable rapid and precise screening of additives. Through machine learning, we identify the molecular size/volume of electrolyte and electrostatic potential maximum (ESPmax) as the two key descriptors influencing the cumulative capacity (CC) performance, achieving a Pearson correlation coefficient of 0.8707 for the log(CC) prediction. This effectively elucidates the regulatory behavior of additive adsorption on the zinc anode surface toward interfacial water molecules, revealing the mechanism by which the number of interfacial water molecules is modulated, thereby inhibiting the hydrogen evolution reaction. Guided by this model, Potassium L-Aspartate additive (PL-As) is identified as a high-performance additive. Consequently, zinc anode achieves an average coulombic efficiency of 99.86% over 5000 cycles and enables the operation of 0.8 Ah pouch cells. This machine learning-driven descriptor fitting and screening approach establishes a new paradigm for developing high-stability aqueous electrolyte additives.

Diglycolamides (DGAs) demonstrated an exceptionally higher affinity for trivalent cations compared to tetravalent ones, attributed to their aggregation behavior, in contrast to the conventional functionalities such as carbamoylmethylphosphine oxide (CMPO), exhibiting a reversal in the affinity. The differing complexation capabilities of the functionalized ionic liquids with DGA and CMPO moieties are reflected in the distinct topology of the electron distribution. Notable additional orbital contributions to the inner s, d, and f subshells of lanthanides suggest a significant covalent character of the complexes. The covalency of the metal-O bonds in the DGA-functionalized ionic liquids was higher than that of the CMPO-functionalized ionic liquids, indicated by Judd-Ofelt parameters. The Eu3+complex of CMPO-TSIL was more asymmetric with one inner sphere water molecule compared to the DGA-TSIL complex with two inner sphere water molecules. The DGA-functionalized ionic liquids formed 1:1, 1:2, and 1:3 M:L species, whereas CMPO-TSIL predominantly formed 1:3 and 1:4 species. The complexation was spontaneous and exothermic. Higher complexation constants for Eu3+ compared to those of Nd3+ were attributed to lanthanide contraction. Shifts in the carbonyl (>C═O) peaks of both DGA-TSIL and CMPO-TSIL confirmed the involvement of carbonyl functionalities in the complexation process. Shifts in the cathodic peak potentials and a reduction in the diffusion coefficient on complexation have been evidenced.

In heme c, protoporphyrin IX employs its vinyl groups to form covalent thioether bonds with the side chains of cysteine residues. The special "heme P460" cofactors in heme c include the additional heme-lysine cross-link. Previous studies have confirmed that the peroxide can drive the formation of a heme-lysine cross-link. Here, we explored the formation mechanism of the heme-Lys cross-link by performing QM/MM calculations. Our calculation results revealed that the Fe(III)-coordinated H2O2 first undergoes a heterolytic O-O cleavage to generate Cpd I, which then employs the water molecule in the active site to carry out the meso-hydroxylation of porphyrin, followed by nucleophilic attack of lysine on the meso-carbon. Importantly, the water molecule generated during the formation of Cpd I is the key to the hydroxylation of the meso-carbon. The pocket residues and the propionic acid side chain of heme not only constitute an encirclement to prevent the escape of the water molecule but also act as a catalytic base/acid to mediate the proton transfer and dehydration processes. Two key factors are responsible for the formation of the heme-Lys cross-link in cytochrome P460s: the fixed water molecule in the reaction center and the suitable orientation of Lys70 for the nucleophilic attack on the unsaturated meso-carbon.

Metal-Organic Frameworks (MOFs) have attracted widespread attention for their applications in water-related contexts. A comprehensive understanding of the molecular-level interactions between water and MOFs is crucial for guiding molecular design and optimizing water-related applications. Water can act as a passive guest, interacting weakly with open metal sites or polar linkers without altering the framework, or as a reactive species that cleaves the dative bonds between inorganic clusters and organic linkers, leading to irreversible degradation. In this work, we uncover a significant impact of water on the metal-linker linkage in UiO-66, a prototype MOFs which is considered highly stable with water. The adsorption of water molecules in UiO-66 results in the displacement of firmly attached carboxylate groups of the linker, thereby transforming them into dangling carboxylate groups. These dangling groups are stabilized by water molecules and μ3-OH through hydrogen bonding. Remarkably, this structural transformation is reversible upon water removal. These findings were elucidated through the integration of multidimensional solid-state NMR, cutting-edge dynamic nuclear polarization (DNP) techniques, and computational calculations. By challenging conventional wisdom, our research has introduced a reversible molecular structure evolution scenario, redefining the understanding of water-MOF interactions.

In this study, we employed the first-principles and real-time time-dependent density functional theory (rt-TDDFT) calculations to investigate the mechanism of visible-light-driven photocatalytic H2 production on transition-metal loaded BTEA-COF. Among 11 metallic elements screened, Pt is identified as the optimal modifier. Pt loading significantly improves the photocatalytic performance by (1) reducing the Gibbs free energy of hydrogen by 38% to 0.19 eV, (2) extending the optical absorption edge from 441 nm (2.81 eV) to 576 nm (2.15 eV) via metal-to-ligand charge transfer, and (3) enhancing the density of photogenerated electrons and suppressing the recombination of charge carriers. Rt-TDDFT simulations of the H2O@Pt/BTEA-COF interface reveal the femtosecond-scale dynamics of water photolysis. The process is dominated by electron transfer from the Pt/BTEA-COF system to the adsorbed water molecule, facilitating O-H bond cleavage at ∼30 fs. The Pt atom acts as a dual-function charge pump, mediating both electron and hole transfer. These findings provide fundamental insights into the superior activity of single-atom catalysts and establish design principles for developing high-efficiency COF-based photocatalytic systems.