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Lithium niobate ( LiNbO 3 , LN) on insulator (LNOI) has emerged as a promising platform for integrated photonics, due to the strong optical confinement and excellent nonlinear optical and electrical characteristics of LN crystal. Focused ion beam (FIB) as a versatile technique has become a typical way to fabricate LNOI microstructures. However, due to the bombardment of Ga + ions during fabrication, the LN lattice is damaged, which would deteriorate the performance of LNOI devices. Thus, the recognition of the damage formed by FIB fabrication is necessary for the control and optimization of the properties of LN microstructures. However, previous studies on this issue have not delved into it from a lattice perspective. Here, we conducted an investigation into the damage inflicted on LN film due to FIB fabrication and the subsequent impact of buffered oxide etching (BOE) treatment on this damage using Raman spectroscopy. Our findings indicate that the interaction between Ga + ions and LN film results in lattice amorphization, as well as a reduction in the ionic bonding and lattice stress within LN. Furthermore, absorption spectra were acquired both before and after BOE treatment, revealing the emergence of additional optical losses attributed to Ga + ions. Notably, these defects responsible for optical losses are predominantly concentrated near the surface of the milled LN film, and BOE treatment proves efficient in their removal. This study contributes to further understanding of the defect structure in LN film after FIB fabrication, as well as repairing the damage and, thus, improving the performance of LN microstructures. [ABSTRACT FROM AUTHOR]

Strong and weak interatomic interactions in chemical and biological systems are ubiquitous, yet how to identify them on a unified theoretical foundation is still not well established. Recently, we proposed employing Pauli energy-based indexes, such as strong covalent interaction and bonding and noncovalent interaction indexes, in the framework of density functional theory for the purpose. In this work, we extend our previous theoretical work by directly employing Pauli energy, Pauli potential, Pauli force, and Pauli charge to simultaneously identify both strong covalent bonding and weak noncovalent interactions. Our results from this work elucidate that using their signature isosurfaces, we can identify different types of interactions, either strong or weak, including single, double, triple, and quadruple covalent bonds, ionic bond, metallic bond, hydrogen bonding, and van der Waals interaction. We also discovered strong linear correlations between Pauli energy derived quantities and different covalent bond orders. These qualitative and quantitative results from our present study solidify the viewpoint that a unified approach to simultaneously identify both strong and weak interactions is possible. In our view, this work signifies one step forward towards the goal of establishing a density-based theory of chemical reactivity in density functional theory. [ABSTRACT FROM AUTHOR]

In the past five years, over 20 types of cyclo-N5− energetic materials (EMs) have been successfully synthesized. Metallic cyclo-N5− EMs exhibit higher density and performance compared to non-metallic cyclo-N5− EMs. However, the mechanisms for such metallic cyclo-N5− EMs remain unexplored. Herein, we performed a thorough quantum chemistry study on the mechanistic pathway for the cyclo-N5− trapped by metal cations in four cyclo-N5− EMs: [Na(H2O) (N5)] · 2H2O, [M(H2O)4(N5)2] · 4H2O (M = Mn, Fe, and Co), by density functional theory methods and transition state theory. During the synthesis process, the cyclo-N5− in the precursor hybrid aromatic compound is susceptible to electrophilic attack by metal cations. This attack disrupts the hydrogen bond interaction surrounding the cyclo-N5−, ultimately leading to the formation of either an ionic bond or a coordination bond between the metal cation and the cyclo-N5−, resulting in an electrophilic substitution reaction. In addition, solvent effects reduce the energy of the ionic bond, thereby promoting the reaction. Our findings will provide valuable insights for future route design and contribute to enhancing the synthesis yield of cyclo-N5− EMs in both theoretical and experimental aspects. [ABSTRACT FROM AUTHOR]

A comprehensive genetic algorithm is used to perform a global search for Cl−(H2O)1–9 and NaCl(H2O)1–9. The structural optimization, energy calculations, vibrational characteristics, and charge distribution were performed at an ab initio high-level theory. Combined with the calculation results of Na+(H2O)1–6 by Wang et al. [Front. Chem. 7, 624 (2019)] in our group, we systematically investigate these three systems at the same theoretical level. A comparison of bond lengths reveals that in Cl−(H2O)n, the inclusion of Na+ to form NaCl(H2O)n reduces the average distance between Cl− and H2O, indicating that Na+ has a stabilizing effect on ionic hydrogen bonds. Conversely, in Na+(H2O)n, the introduction of Cl− weakens the interactions between Na+ and H2O. In the NaCl(H2O)1–9 structures searched by the genetic algorithm, the ground-state configurations correspond to contact ion pairs, and the solvent-separated ion pair structures appear when n = 7. Furthermore, the anharmonic corrected infrared spectra of Cl−(H2O)1–5 and NaCl(H2O)1–4 exhibit good agreement with the experimental results. According to charge analysis of NaCl(H2O)n, it is observed that charge transfer primarily occurs from Cl− to H2O, resulting in the presence of negative charges on the water molecules. These findings are helpful to understand the effects of Na+ and Cl− on hydrated clusters at the molecular level. [ABSTRACT FROM AUTHOR]

Hydrophilic semiconductor quantum dots (QDs) with emission in the second near-infrared window (NIR-II) have been widely studied in bioimaging applications. In such cases, QDs are usually dispersed in water. As is known, water has strong absorbance in the NIR-II region. However, investigations on the interaction between NIR-II emitters and water molecules are ignored in previous studies. Herein, we synthesized a series of mercaptoundecanoic acid-coated silver sulfide (Ag2S/MUA) QDs with various emissions that partially or completely overlapped with the absorbance of water at 1200 nm. By constructing a hydrophobic interface of cetyltrimethylammonium bromide (CTAB) with MUA on the Ag2S QDs surface via forming an ionic bond, significant enhancement of Ag2S QDs photoluminescence (PL) intensity was observed, as well as a prolonged lifetime. These findings suggest that there is an energy transfer between Ag2S QDs and water in addition to the classical resonance absorption. Transient absorption and fluorescence spectra results revealed that the increased PL intensities and lifetime of Ag2S QDs originated from the suppressed energy transfer from Ag2S QDs to the water due to the CTAB bridged hydrophobic interfaces. This discovery is important for a deeper understanding of the photophysical mechanisms of QDs and their applications. [ABSTRACT FROM AUTHOR]

First-principles calculations are performed, revealing a significant enhancement of the piezoelectric properties of wurtzite Zn 3 6 O 3 6 upon the incorporation of a single Cu atom. Research has demonstrated that the piezoelectric constant d 3 3 reaches its maximum value at a doping concentration of 1.4% for Cu atoms. The lattice parameters a and c of Zn 3 6 O 3 6 are decreased and the piezoelectric strain coefficient d 3 3 is increased by replacing one Cu atom in Zn 3 6 O 3 6 . It is found that elastic softening is the primary factor responsible for the increase of d 3 3 in Zn 3 5 Cu1O 3 6 . By differential charge density analysis, it is found that the covalency between Cu–O bonds is lower than that of Zn–O bonds, and the covalent bonding characteristics are weakened. Bader charge analysis shows that the charge of Cu is higher than that of Zn, indicating a more significant ionic bonding feature than that of Zn. Thus, a weaker covalent and stronger ionic bond are considered to play an essential role in promoting elastic softening for ZnO, which eventually promotes a significant enhancement in piezoelectric properties. [ABSTRACT FROM AUTHOR]

The mechanical properties of halide perovskites have been attracting ever-increasing interest for their significant importance in future industrial applications. However, studies focused on the effect of B-site substitution of molecular perovskites on their mechanical properties are rare, which makes it favorable to shed light on their fundamental structure--mechanical property relationships. Here, using isostructural halide perovskites, [C4H12N2][BCl3]•H2O(B=NH4+;K+), constructed by ionic bonds and hydrogen bonds, respectively, as the model systems, we investigate their mechanical properties through high-pressure synchrotron X-ray diffraction experiments and density functional theory calculations. Owing to the similar sizes of NH4+ and K+, the two compounds possess almost identical cell parameters and frameworks. Upon compression, the two perovskites exhibit analogous behavior except for slight differences in the shrinkage ratio of principal axes and the onset pressure of amorphization. The fitted bulk moduli of [C4H12N2][KCl3]•H2Oand[C4H12N2][NH4Cl3]•H2O are 43.89 and 27.28 GPa, respectively. These results demonstrate that the simple replacement of K+ by NH4+ can significantly reduce the structural rigidity of the corresponding compounds, which is ascribed to the weaker strength of NH4...Cl hydrogen bonds than that of K-Cl bonds. [ABSTRACT FROM AUTHOR]

The mechanical properties of halide perovskites have been attracting ever-increasing interest for their significant importance in future industrial applications. However, studies focused on the effect of B-site substitution of molecular perovskites on their mechanical properties are rare, which makes it favorable to shed light on their fundamental structure--mechanical property relationships. Here, using isostructural halide perovskites, [C4H12N2][BCl3]•H2O(B=NH4+;K+), constructed by ionic bonds and hydrogen bonds, respectively, as the model systems, we investigate their mechanical properties through high-pressure synchrotron X-ray diffraction experiments and density functional theory calculations. Owing to the similar sizes of NH4+ and K+, the two compounds possess almost identical cell parameters and frameworks. Upon compression, the two perovskites exhibit analogous behavior except for slight differences in the shrinkage ratio of principal axes and the onset pressure of amorphization. The fitted bulk moduli of [C4H12N2][KCl3]•H2Oand[C4H12N2][NH4Cl3]•H2O are 43.89 and 27.28 GPa, respectively. These results demonstrate that the simple replacement of K+ by NH4+ can significantly reduce the structural rigidity of the corresponding compounds, which is ascribed to the weaker strength of NH4...Cl hydrogen bonds than that of K-Cl bonds. [ABSTRACT FROM AUTHOR]

Copper(I) halide cluster‐based coordination compounds have attracted significant attention in the development of novel scintillators due to their mild synthesis methods, high luminescence efficiency, tunable emission wavelength, high‐Z element incorporation, and large structural diversity. However, a major obstacle for these crystalline materials with covalent/coordination network structures is their insolubility, which poses significant challenges for the low‐cost and large‐scale production of scintillation films. In this study, copper(I) iodide and benzotriazole derivative ligands with diverse cationic substituents are employed to fabricate all‐in‐one (AIO) colloidal copper(I) iodide cluster‐based scintillator suspensions. These suspensions, characterized by distinctive ionic and coordination bonds, are synthesized via confined growth in the presence of polyvinylpyrrolidone (PVP). Furthermore, they demonstrate exceptional compatibility with polymer matrices, facilitating the production of uniform and flexible scintillation films with highly efficient radioluminescence through blade coating. The resulting films achieved an excellent spatial resolution of 17 lp mm−1. This surfactant‐assisted fabrication method for colloidal scintillators, combined with microelectronic printing for film preparation, demonstrates significant potential for developing flexible scintillation films for high‐resolution X‐ray imaging. [ABSTRACT FROM AUTHOR]

This work investigates the effects of irradiation on Ti 3 SiC 2 -containing interphase or coating in SiC f /SiC using a cooperative experiment involving H and He ions. SiC/TiC/Ti 3 SiC 2 /Ti 5 Si 3 C x and SiC/Ti 3 SiC 2 were irradiated at room temperature and then annealed at 320 °C for 24 h. Results showed the lattice swelling in all phases. With increasing irradiation dose, SiC and Ti 5 Si 3 C x underwent amorphization, while TiC and Ti 3 SiC 2 remained stable due to their ionic bonds. Annealing facilitated the migration of collision products and H, He ions to grain boundaries and phase interfaces, reducing lattice swelling rates of TiC and Ti 3 SiC 2. The SiC/TiC interface displayed ion cluster accumulation, impacting the interface bonding strength, while the Ti 3 SiC 2 /Ti 5 Si 3 C x interface exhibited the formation of cavities. Conversely, the TiC/Ti 3 SiC 2 and SiC/Ti 3 SiC 2 interfaces were stable. These findings indicate that interphase or coating containing Ti 3 SiC 2 monolithic or TiC/Ti 3 SiC 2 multilayered structures possess strong irradiation resistance. [ABSTRACT FROM AUTHOR]

To study the interfacial properties of Ag/In2O3, the interfacial binding energy, interfacial adhesion work, and interfacial electronic properties of Ag/In2O3 were calculated based on the first principles of density functional theory. The results show that the surface energy of 50 layers of In2O3 (110)-O and 48 layers of In2O3 (111)-O is small and the surface is stable. Ag(111) surface thickness of 10 layers is the most stable, based on which the Ag/In2O3 interface is established. In the established Ag/In2O3 interface, the Ag(111)/In2O3(110)-O interface has good stability, high interface bonding strength, and metallic characteristics. When the interface spacing is 3.0 Å, the interface stability is good. The charge redistribution at the interface results in the change of the density of the local atomic states, in which the change of Ag and O atoms is more obvious. In addition, the Ag/In2O3 interface is mainly bound by ionic bonds, and the interface part is well bound. [ABSTRACT FROM AUTHOR]

Magnesite is calcined to obtain active magnesium oxide, which is subsequently used in chemical reactions. There are high energy consumption and disorderly carbon dioxide emissions. Herein, direct utilization of all the elements in magnesite without roasting was achieved via surface modification activation technology. Sodium oleate was used as an activator; the reaction was carried out at 95°C for 4 h under alkaline conditions, and 60 mL sulfuric acid was added, resulting in the production of 9.5 g MgCO3·3H2O, 192.3 g magnesium sulfate heptahydrate, and 26.6 g wollastonite. The recovery rate reached 100%, while the conversion rate of magnesium oxide reached 83.6%. Density functional theory simulations revealed calcium and magnesium as the primary active sites. Sodium oleate adsorbs onto the magnesite surface through electrostatic adsorption and hydrogen bonding. Ionic and hydrogen bonds formed with Mg, Ca, and O in magnesite, which reduced the activation energy of magnesite. This paper presents a method for the chemical utilization of magnesite without roasting all the elements. [ABSTRACT FROM AUTHOR]

In this work, we present theoretical calculations of the structural, electronic, optical and thermoelectric properties of the perovskite oxides LaMO3 (M = Ga or In) using density functional theory (DFT) with GGA–PBE approximation, as implemented in the ABINIT code. The cubic crystal structure of LaMO3 (M = Ga or In) compounds changes and its volume increases when the Ga atom is replaced by an In atom. In addition, negative formation energies suggest the thermodynamic stability of the studied compounds. Electron charge densities reveal an ionic bond between La and O, while the bond between M and O appears covalent. Electronic properties showed the indirect semiconducting behavior of LaGaO3 and LaInO3 perovskites. The calculated indirect bandgaps Eg (R–Γ) are found to be 3.34eV for LaGaO3 and 2.08eV for LaInO3. In addition, optical characteristics are determined in terms of real ε1(ω) and imaginary ε2(ω) parts of dielectric constant ε(ω), refractive index n(ω), absorption coefficient α(ω), reflectivity R(ω), energy loss function L(ω), optical conductivity σ(ω) and transmittance T(ω) are also studied. Optical absorption of light energy has been observed in both the visible and ultraviolet ranges, increasing the importance of the studied materials for optoelectronic applications. Finally, the thermoelectric performance of LaMO3 (M = Ga or In) materials has been explored using the Boltzmann transport theory implemented in the BoltzTraP software package. [ABSTRACT FROM AUTHOR]

Si is an important semiconductor material in the development of modern industry. With the miniaturization trend of semiconductor devices, the size of Si has reached the cluster size. The search for stable Si clusters is an important issue. In this work, the electronic structures and stability mechanism of the W@Si12 cluster are calculated by the first-principle calculations. Different from a C2v hexacapped trigonal prism structure of Si12, the W@Si12 cluster presents an embedded hexagonal prism structure with D6h symmetry. The addition of W atom leads to a higher stability. The molecular orbitals show obvious superatomic characteristics for the W@Si12 cluster, and their energy levels are more degenerate than that of the Si12 cluster. The population analysis indicates that a total charge of 2.21e is transferred from Si atoms to the center W atom, which suggests an ionic bond for W-Si. The electron localization function further proves a covalent bond for Si–Si. The enhanced stability of the W@Si12 cluster is attributed to the combination of the ionic and covalent bonds. [ABSTRACT FROM AUTHOR]

A new type of material, organic salts in the crystal and crystalline powder state, with both excitation wavelength dependent (Ex‐De) fluorescence and Ex‐De phosphorescence under ambient conditions have been reported. The single component triphenylsulfonium chloride displays tunable fluorescent colors ranging from light purple to sky blue and tunable afterglow colors varying from green to yellowish green, to yellow (lifetimes: 57, 141, 66 ms, afterglow lasting for 2.1, 2.0, 2.3 s). The relationship between the structure and luminescence performance of 17 sulfonium salt derivatives confirms the pivotal roles of both the anions and the electronic and steric effect of substituent factors for luminescence. Single‐crystal analysis reveals that unique ionic bonding and intermolecular interaction can promote an ordered arrangement of organic salts in a crystal state, which then can facilitate molecular aggregation for phosphorescence generation. Theoretical calculations have also confirmed this viewpoint. More importantly, these sulfonium salt derivatives can be used for advanced multimodal anti‐counterfeiting and mitochondrial imaging, respectively. This study has not only expanded the scope of Ex‐De materials but also extended their applications. [ABSTRACT FROM AUTHOR]

The interfacial bonding state between each oxide and the silver matrix in AgCuOIn2O3SnO2 electrical contact materials remains unclear. To address this, first‐principles calculations using density‐functional theory are employed to establish the low‐index surfaces of Ag and SnO2 and perform convergence tests. Computational results reveal that the Ag (111) surface and the SnO2(110)‐O surface exhibit the highest stability among their respective low‐index surfaces. Consequently, these surfaces are chosen to form the interfacial model, and their atomic structure, adhesion work, and interfacial energies are systematically analyzed. The results demonstrate that the stability and interfacial bonding strength of the Ag(111)/SnO2(110)‐O interface are high, exhibiting metallic properties and strong conductivity. Moreover, at an interface spacing of d0 = 2.4 Å, the interface stability is optimal. The redistribution of charge at the interface induces significant changes in the local atomic density of states, particularly noticeable in the Ag and O atoms. Additionally, the Ag/SnO2 interface is predominantly bonded through ionic interactions, contributing to its robust bonding. [ABSTRACT FROM AUTHOR]

ABSTRACT The occurrence of hydrogen embrittlement often leads to significant fracturing in materials. Thus, a comprehensive understanding of the interactions of hydrogen and its effects on material properties is essential. In this study, first‐principle calculations based on density functional theory are conducted to investigate the adsorption and diffusion characteristics of hydrogen at the Ni/Ni3Al(γ/γ') interface of a Ni‐based single‐crystal superalloy. The results show that hydrogen can stably adsorb onto the γ/γ′ interface, nearby octahedral interstitial sites, and tetrahedral interstitial sites in the γ‐phase. Analysis of the density of states and charge density confirms that the hydrogen atoms formed covalent bonds and ionic bonds with nearby Al atoms. A transition state structure search based on linear synchronous transit (LST) and quadratic synchronous transit (QST) models is utilized to calculate the diffusion paths and energy barriers of the hydrogen atoms between the stable adsorption sites near the interface. In addition, the permeation characteristics of hydrogen atoms at the interface are analyzed. Furthermore, it is confirmed that hydrogen atoms entering the matrix from the interface preferentially occupy the positions of the regular octahedral interstitial sites, diffuse towards adjacent regular 6Ni octahedral interstitial sites through the inclined octahedral interstitial sites between the atomic layers, and converge at the interface. [ABSTRACT FROM AUTHOR]

Hydrogen storage exploration in carbon-based materials is pivotal for advancing energy technologies. This study employs first-principles Density Functional Theory (DFT) calculations, utilizing the PBE functional with the VASP code, to investigate the 4-6-8 biphenylene (C468) and its derivatives, a distinctive 2D carbon structure. Both pristine C468 and its titanium-decorated variants (1TiC468 and 2TiC468) are analyzed. 1TiC468 and 2TiC468 exhibit maximum hydrogen molecule accommodation of up to 12 and 24, achieving gravimetric densities of 6.713 wt% and 11.188 wt%, respectively, with adsorption energies ranging from −0.132 eV/H 2 to −0.399 eV/H 2. These gravimetric values align with or surpass DOE guidelines. Additionally, comparative analysis indicates enhanced hydrogen adsorption due to Ti presence in C468. Molecular dynamics (MD) and phonon dispersion studies confirm the stability of mTiC468 (m = 1 and 2) systems at 300K. These findings underscore the potential of Ti-decorated C468 as hydrogen storage candidates, expanding the applications of carbon-based materials in energy storage. [Display omitted] • TiC468 and 2TiC468 have been investigated as H 2 storage materials. • Gravimetric wt.% of TiC468.12H 2 is 6.713, and 2TiC468.24H 2 is 11.188. • Strong TiC468 ionic bond confirmed by Bader charge and charge difference analysis. • H–H bonds suggest non-dissociative state of adsorbed H 2 under Ti interaction. • Av. T d of 338K in TiC468.nH 2 and 307K in 2TiC468.nH 2 fall within the suitable range. [ABSTRACT FROM AUTHOR]

AbstractSelf-healing materials have garnered significant attention for their potential to heal damage when it occurs. Elastomers, particularly natural rubber, have been a focal point of extensive research in the realm of self-healing materials. The ability of self-healing in natural rubber not only promises to extend the service life of rubber-based products but also offers new avenues for recyclability and reprocessability, contributing to environmental protection efforts. A key challenge in the self-healing of natural rubber has been to enhance its self-healing capabilities without compromising its mechanical properties. As a result, various self-healing mechanisms such as hydrogen bond, Diels–Alder (D-A) reaction, disulfide bond, imine bond, and ionic bond have been thoroughly investigated. Among these mechanisms, reversible ionic bonds or ionic interactions have emerged as particularly influential in facilitating the self-healing of natural rubber. This mechanism is easily incorporated into the structure of natural rubber due to its high stability, enabling natural rubber to exhibit promising self-healing properties. This review delves into a comprehensive statistical analysis of numerous published articles and focuses on the exploration of the ionic bonding mechanism in the context of self-healing in natural rubber. Additionally, it provides a succinct introduction to specialized tests designed to assess the self-healing in natural rubber focusing on related methods for ionic bonds mechanism evaluation, namely swelling test and healing efficiency test. [ABSTRACT FROM AUTHOR]

Magnetic Fe3O4 nanoparticles (MNPs) functionalized with (3-aminopropylo)trietoksysilan (APTES) or N-carboxymethylchitosan (CMC) were proposed as nanocarriers of methotrexate (MTX) to target ovarian cancer cell lines. The successful functionalization of the obtained nanostructures was confirmed by FT-IR spectroscopy. The nanoparticles were characterized by transmission electron spectroscopy (TEM) and dynamic light scattering (DLS) techniques. Their potential zeta, magnetization, and hyperthermic properties were also explored. MTX was conjugated with the nanocarriers by ionic bonds or by amide bonds. The drug release kinetics were examined at different pH and temperatures. The MTT assay showed no toxicity of the MNPs[APTES] and MNPs[CMC]. Finally, the cytotoxicity of the nanostructures with MTX attached towards the ovarian cancer cells was measured. The sensitivity and resistance to methotrexate was determined in simplistic 2D and spheroid 3D conditions. The cytotoxicity tests of the tested nanostructures showed similar values for inhibiting the proliferation of ovarian cancer cells as methotrexate in its free form. Conjugating MTX with nanoparticles allows the drug to be directed to the target site using an external magnetic field, reducing overall toxicity. Combining this approach with hyperthermia could enhance the therapeutic effect in vivo compared to free MTX, though further research on advanced 3D models is needed. [ABSTRACT FROM AUTHOR]

In this study, imidazolium‐based multifunctional ionic polymer (IP 1–IP 3) series, co‐incorporated with phenolic hydroxyl groups as hydrogen bond donors (HBDs) and Cl− as nucleophiles, are synthesized by a facile quaternization method. The physicochemical characterizations of these IPs are systematically examined by using FTIR, XPS, BET, TGA, CO2‐TPD, SEM with elemental mapping and TEM methods. Their catalytic activities are evaluated toward the conversion of carbon dioxide (CO2) and epoxides into cyclic carbonates under solvent‐ and additive‐free environments. Apart from the synergy effect between HBDs and Cl−, it is found that the types of the spacer linking the two imidazole units in the diimidazole precursors (L1–L3) also play an important role in the catalytic activity. And IP 2, with a pyridine spacer as a Lewis base site, exhibits the best catalytic performance under solvent‐free mild conditions i. e., atmospheric pressure CO2, 80 °C, and 5 h. Notably, the catalyst demonstrates a good substrate applicability. Furthermore, IP 2 exhibited good reusability, stability, and it can be recycled for ten successive runs with stable and potential catalytic activity. This study provides an alternative route to construct IPs with efficient activity for CO2 catalytic conversion and fixation under mild‐conditions. [ABSTRACT FROM AUTHOR]

Organometallics are chemical compounds that consist of carbon-metal linkages. They have emerged as a result of the combination of organic and inorganic chemistry and exhibit a stable metal-carbon bond in solution. These compounds possess properties that lie between those of ionic and covalent bonds, making them highly significant in various industries. The fact that organometallics are present in all living organisms further emphasises their importance. In this overview, we will explore general reactions, such as substitution and insertion reactions, as well as different techniques for creating organometallic complexes. Additionally, we will provide a brief synthesis review of various types of organometallic complexes, including carbonyls, hydrides, alkyls, carbenes, and carbines. Organometallic compounds find extensive applications in stoichiometric chemical processes in both research and industry. Moreover, they serve as catalysts to enhance these reactions, making them more than just theoretical compounds. For example, organotin compounds are widely used as fire retardants, polymers, medications, insecticides, and stabilizers for polyvinyl chloride. [ABSTRACT FROM AUTHOR]

The weak intermolecular forces of hydrogen‐bonded organic frameworks (HOFs) make it relatively difficult to synthesize and design HOFs with superprotonic conductivity and robustness. The self‐assembly of ionic hydrogen bonding organic frameworks (iHOFs) through acid–base pairing strategies are possible on account of the rich hydrogen bonding, strong ionic bonding, and π–π stacking interactions and so on. Herein, a case of iHOF (iHOF‐16) with a three‐dimensional (3D) hydrogen bonding network is reported, the doughty ionic bond interactions in the structure and π–π stacking interactions between layers make it exhibits excellent thermal and chemical stability, it can maintain high crystallinity and robust structure even under extreme conditions. Importantly, iHOF‐16 exhibits highly anisotropic proton conductivity of 0.388, 5.56 × 10−3, and 3.25 × 10−4 S cm−1 in the direction of a‐axis, b‐axis, and c‐axis, respectively. The proton transfer paths of single crystal on each axis are calculated using density functional theory (DFT) and, supported by joint experimental–theoretical calculations, protons are most easily transported in the a‐axis direction resulting in superprotonic conductivity. The present study provides a promising approach for the design of stable superprotonic conductivity materials through a simple yet effective charge‐assisted synthesis strategy. [ABSTRACT FROM AUTHOR]

Wood-based laminated composites with excellent strength and toughness have attracted much attention, but it is a challenge to process fast-growing natural poplar wood with poor mechanical properties into high-performance laminated composites without the use of adhesives. In this study, natural poplar wood was delignified and TEMPO-oxidized by a "top-down" strategy to obtain a wood scaffold with a cellulose content of up to 98%, which was then used as a substrate and impregnated with Ca2+ and PVA to form a large number of hydrogen and ionic bonds within the wood. Finally, under the action of hot pressing, laminated composites with high tensile strength (237 MPa), flexural strength (246 MPa) and impact toughness (50.45 KJ/m2) were obtained, which also displayed excellent thermal stability and water resistance. This work demonstrates that the utilization of renewable fast-growing poplar wood as a substrate and glue-free bonding method can produce low-cost, sustainable and high-performance wood-based laminated composites. [ABSTRACT FROM AUTHOR]

The control of noncarbon stereogenic centers is of profound importance owing to their enormous interest in bioactive compounds and chiral catalyst or ligand design for enantioselective synthesis. Despite various elegant approaches have been achieved for construction of S‐, P‐, Si‐ and B‐stereocenters over the past decades, the catalyst‐controlled strategies to govern the formation of N‐stereogenic compounds have garnered less attention. Here, we disclose the first organocatalytic approach for efficient access to a wide range of nitrogen‐stereogenic compounds through a desymmetrization approach. Intriguingly, the pro‐chiral remote diols, which are previously not well addressed with enantiocontrol, are well differentiated by potent chiral carbene‐bound acyl azolium intermediates. Preliminary studies shed insights on the critical importance of the ionic hydrogen bond (IHB) formed between the dimer aggregate of diols to afford the chiral N‐oxide products that feature a tetrahedral nitrogen as the sole stereogenic element with good yields and excellent enantioselectivities. Notably, the chiral N‐oxide products could offer an attractive strategy for chiral ligand design and discovery of potential antibacterial agrochemicals. [ABSTRACT FROM AUTHOR]

Low‐energy visible‐light‐activated carbon dots (CDs)‐based afterglow materials are difficult to realize due to the inherent aromatic carbon with high‐energy absorption and the lack of effective regulation. Here, a new strategy for visible‐light‐activated CDs is proposed by combining dual‐confinement and surface‐ionization, which employs NaOH for additional confinement and surface ionization of CDs in a single boric acid (BA) matrix. The comparison experiments show that: i) shifting the excitation from UV‐light to vis‐light is realized by enhancing the low‐energy surface states n→π* transition of the CDs by surface ionization of NaOH. ii) CDs are additionally protected by a more stable Na─O ionic bond after NaOH confinement, resulting in a brighter afterglow. iii) the energy gap (ΔEST) between the lowest singlet and triplet states is gradually shortened as increasing NaOH content, facilitating intersystem crossing, prolonging the lifetime of triplet excitons and efficiency. Further, vis‐light‐excited colorful afterglow powders are fabricated based on Förster Resonant Energy Transfer by combining the fluorescent dye 5‐carboxytetramethylrhodamine. Finally, advanced white‐light‐activated time‐resolved anti‐counterfeiting and intelligent traffic flashing signs are realized. The work may shed new light on the design of low‐energy‐activated afterglow materials and broaden the application scenarios in the daily lives of human society. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI3 perovskite semiconductor is attractive for deep‐red light‐emitting diodes (LEDs) because of its high photoluminescence, good thermal stability, excellent charge transport, and solution processability. However, the metastable phase of optically active CsPbI3 hinders the fabrication of efficient and bright deep‐red LEDs. Herein, a multifunctional ionic ligand regulation strategy using (2‐hydroxy‐5‐methylphenyl) triphenyl‐phosphonium iodide and 3‐(N, N‐dimethyloctylammonio) propanesulfonate is reported to regulate the optically active CsPbI3 crystallization and thus obtain high‐quality γ‐CsPbI3 thin films. The high crystallinity and preferential orientation of γ‐CsPbI3 arise from the strong bonding between the ionic ligands and ionic lead halide clusters. The obtained γ‐CsPbI3 thin films also possess suppressed defect densities, high luminescence, and high stability. Using this high‐quality thin film, an efficient and bright deep‐red LED with a peak external quantum efficiency of 13.34% and a maximum luminance of 2110 cd m−2 is successfully fabricated. The operational lifetime of the fabricated LED (time to half of the initial brightness, T50) reaches up to 40 min under a high current density of 50 mA cm−2 (corresponding to the initial brightness of 200 cd m−2). [ABSTRACT FROM AUTHOR]

2D compounds exfoliated from weakly bonded bulk materials with van der Waals (vdW) interaction are easily accessible. However, the strong internal ionic/covalent bonding of most inorganic crystal frameworks greatly hinders 2D material exfoliation. Herein, we first proposed a radical/strain‐synergistic strategy to exfoliate non‐vdW interacting pseudo‐layered phosphate framework. Specifically, hydroxyl radicals (⋅OH) distort the covalent bond irreversibly, meanwhile, H2O molecules as solvents, further accelerating interlayered ionic bond breakage but mechanical expansion. The innovative 2D laminar NASICON‐type Na3V2(PO4)2O2F crystal, exfoliated by ⋅OH/H2O synergistic strategy, exhibits enhanced sodium‐ion storage capacity, high‐rate performance (85.7 mAh g−1 at 20 C), cyclic life (2300 cycles), and ion migration rates, compared with the bulk framework. Importantly, this chemical/physical dual driving technique realized the effective exfoliation for strongly coupled pseudo‐layered frameworks, which accelerates 2D functional material development. [ABSTRACT FROM AUTHOR]

Transglutaminase (TGase)-catalyzed crosslinking has gained substantial traction as a novel strategy for reducing allergenic risk in food proteins, particularly within the realm of hypoallergenic food production. This study explored the impact of TGase crosslinking on conformational changes in a binary protein system composed of soy protein isolate (SPI) and sodium caseinate (SC) at varying mass ratios (10:0, 7:3, 5:5, 3:7 (w/w)). Specifically, the immunoglobulin E (IgE) binding capacity of soy proteins within this system was examined. Prolonged TGase crosslinking (ranging from 0 h to 15 h) resulted in a gradual reduction in IgE reactivity across all SPI-SC ratios, with the order of IgE-binding capability as follows: SPI > SPI5-SC5 > SPI7-SC3 > SPI3-SC7. These alterations in protein conformation following TGase crosslinking, as demonstrated by variable intrinsic fluorescence, altered surface hydrophobicity, increased ultraviolet absorption and reduced free sulfhydryl content, were identified as the underlying causes. Additionally, ionic bonds were found to play a significant role in maintaining the structure of the dual-protein system after crosslinking, with hydrophobic forces and hydrogen bonds serving as supplementary forces. Generally, the dual-protein system may exhibit enhanced efficacy in reducing the allergenicity of soy protein. [ABSTRACT FROM AUTHOR]

Reactive air wetting and brazing of AlN ceramic were performed using Ag-(0 20)at%CuO fillers. The wettability, joint mechanical properties and microstructural evolution were investigated, and the related surface energies, interfacial stability and electronic properties of Ag-CuO/AlN system were evaluated comprehensively by density functional theory (DFT) calculations. With the CuO content increasing, the contact angle of Ag-CuO/AlN system reduces significantly from over 120° to <10°. The variation of joint strength is closely related to the formation of interfacial Al 2 O 3 layer and the thickness of Ag layer, and the average shear strength of AlN/AlN joint arrives at the maximum of 57.5 MPa. Moreover, the DFT calculations demonstrate that the Ag(111)/Al 2 O 3 (001) and Ag(111)/CuO(001) interfaces present stronger and more stable interfacial bonding than the Ag(111)/AlN(001) interface owing to the formation of O-Ag ionic bond, suggesting that the Ag/AlN interface can be effectively strengthened due to the addition of CuO and in-situ oxidation of AlN substrate. • Wettability and interfacial behavior of Ag-CuO/AlN system. • Microstructural evolution and mechanical properties of AlN/AlN RAB joints. • Interfacial stability and electronic properties of Ag/(AlN, CuO, Al 2 O 3) interfaces. [ABSTRACT FROM AUTHOR]

The improvement of photovoltaic and stability performance of tin (Sn)‐based halide perovskite solar cells is impeded by notorious oxidation issues and Anderson localization. Despite previous implements in antioxidation through the incorporation of Lewis base additives, there still exist ongoing uncertainties surrounding its complex interaction mechanisms. A perplexing phenomenon regarding accelerated oxidation in acrylic acid is discovered that deviates from conventional Lewis base–acid reaction. The underlying insights into the deprotonation of acrylic acid followed by the formation of a "tripod" ionic bonding form are provided, which results in amplifying the delocalization effect of electrons of Sn2+. Furthermore, with the assistance of acrylamide and acrolein, synergistic enhancement in terms of the antioxidation and suppression of Anderson localization can be achieved — a concept referred to as "Dual Synergistic Engineering". This suppresses the oxidation of Sn2+ and reduces Sn4+ content by ≈76%. Meanwhile, the diffusion length is prolonged significantly from 195.9 to 458.9 nm. The optimized all‐inorganic Sn/Pb‐based perovskite solar cells exhibit a power conversion efficiency of above 14% with enhanced stability. These findings provide an alternative viewpoint for comprehending the impact of chemical interaction on oxidation and crystal growth in Sn/Pb‐based perovskites. [ABSTRACT FROM AUTHOR]

In this work, a two‐step activated swelling technique was effectively employed to successfully synthesize monodisperse porous poly(styrene‐divinylbenzene) (PS‐DVB) particles. Diazoresin (DR) transform an ionic bond into a covalent bond by photoreaction. Under ultraviolet irradiation, DR was used to covalently attach dichlorophenyl isocyanate to sulfonated PS‐DVB microspheres. The novel photo‐crosslinking reaction effectively overcomes the toxicity issues associated with conventional coupling agents and enables green production of chromatographic fillers. Modified PS‐DVB particles were indeed commonly used as filler material for the separation of chiral compounds by high performance liquid chromatography (HPLC). The porous modified microspheres designed effectively separate benzoone, DL‐mandelic acid, 2‐phenylcyclohexanone, ibuprofen, 2‐hydroxyl flavone, DL‐cysteine, chloraniline maleate, hesperidin, and other chiral compounds by 100 mm column. It is noteworthy that the isocyanate‐chitin modified microspheres are effective in separating chiral drugs (1000 μg/mL) within 5 min. Compared with ordinary microspheres, porous isocyanate‐chitin modified microspheres showed better separation efficiency under the same conditions. The enhancement is attributed to the increase in their specific surface area. Consequently, they are a better choice of chromatographic packing matrix. [ABSTRACT FROM AUTHOR]

CeO2 has high elastic modulus and thermal stability, as well as good surface effects, making it ideal as a reinforcement for aluminum matrix composites. In this paper, the interfacial relationships between Al and CeO2 was studied by first-principles calculation, and the nucleation mechanism of aluminum matrix growth on CeO2 substrate was discussed. First, the Al/CeO2 interface matching crystal surface was identified as the Al(111)/CeO2(111) interface. Then, the surface work function was calculated for all surfaces constituting the Al(111)/CeO2(111) interface, and the results showed that the Al(111) loses charge more easily than CeO2(111). Subsequently, the interface energy and work of adhesion of the Al(111)/CeO2(111) interface were calculated, and the results showed that the interface energy of O1–Al was the smallest (0.07 J/m2), the work of adhesion of O2 interface energy of O1–Al was the smallest (0.07 J/m2), the work of adhesion of O2–Al was the largest (9.36 J/m2)Al was the largest (9.36 J/m2). Finally, the combined properties of the Al(111)/CeO2(111) interface were analyzed by the electronic properties at the interface, and the results showed that The Al(111)/CeO2(111) interface is a mixture of ionic and covalent bonds. Therefore, the calculated results confirm that the effectiveness of CeO2 as a heterogeneous nucleation substrate for Al. This study provides a theoretical basis for the nucleation mechanism of the heterogeneous nucleation interface between CeO2 and aluminum matrix. [ABSTRACT FROM AUTHOR]

As a novel conceptual synthesis of a metal–organic framework (MOF)-based proton conductor, UiO-66 based on a pyridinedicarboxylic acid phosphate (PyDC-PA) ion pair linker has been developed, in which the phosphoric acid is fixed to the N donor moiety of pyridine via an ionic bond. [ABSTRACT FROM AUTHOR]

Nanobiocatalysts (NBCs), which merge enzymes with nanomaterials, provide a potent method for improving enzyme durability, efficiency, and recyclability. This review highlights the use of eco-friendly synthesis methods to create sustainable nanomaterials for enzyme transport. We investigate different methods of immobilization, such as adsorption, ionic and covalent bonding, entrapment, and cross-linking, examining their pros and cons. The decreased environmental impact of green-synthesized nanomaterials from plants, bacteria, and fungi is emphasized. The review exhibits the various uses of NBCs in food industry, biofuel production, and bioremediation, showing how they can enhance effectiveness and eco-friendliness. Furthermore, we explore the potential impact of NBCs in biomedicine. In general, green nanobiocatalysts are a notable progression in enzyme technology, leading to environmentally-friendly and effective biocatalytic methods that have important impacts on industrial and biomedical fields. [ABSTRACT FROM AUTHOR]

High dielectric biobased composites of TEMPO-oxidized cellulose nanofibers (TOCNFs) reinforced with cationic modified barium titanate (BTO) nanoparticles were fabricated in this work. In order to greatly eliminate the agglomeration of the nanofiller and improve the dielectric properties of the resulting film, the modification of BTO was achieved via the cationization with an etherifying agent on the basis of cladding polydopamine around BTO. The results showed that the modified BTO nanofiller had a good interfacial compatibility and dispersion in the TOCNF matrix due to the ionic and hydrogen bonds formed between the cationic modified BTO and anionic TOCNFs. Meanwhile, the modified BTO reinforced composites exhibited better dielectric properties. Especially, the composite film with 40 wt% modified BTO exhibited an ultrahigh dielectric constant of 116.2 (at 1 kHz) and a breakdown strength of 57.7 kV/mm, which was 696% and 51.4% respectively higher than that of pure TOCNF film. It was noticed that the hydrophobicity of the composite films was also slightly improved without sacrificing its mechanical strength. [ABSTRACT FROM AUTHOR]

Lead is a global priority pollutant. Its presence in aquatic systems is harmful to the human health. Fluoride is essential to the human body, especially in dental health. However, excess fluoride in the body can lead to serious health concerns. Therefore, a simple approach to monitoring lead and fluoride in environmental samples is paramount. In this study, we synthesized N and S co-doped carbon quantum dots under the hydrothermal method by employing citric acid, glutamine, and sodium sulphide (Na2S) as precursors. Characterization of the developed nanosensor was carried out using Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) spectrophotometer, ultraviolet–visible spectroscopy (UV–Vis), and X-ray diffraction (XRD). The as-prepared nanosensor is spherical with an average particle diameter of 3.45 ± 0.86 nm and emits light in the green region of the spectrum. This material was employed as an 'on–off' and 'off–on' fluorescent sensor to determine Pb2+ and F− rapidly and selectively. The fluorescence was quenched (turned off) in the presence of Pb2+ because of the strong interaction between Pb2+ ions and the surface functional groups of the as-synthesized material. Subsequently, the quenched fluorescence of the N, S-CQDs + Pb2+ system was restored (turned on) upon the introduction of F− ions, owing to the formation of ionic bonds between Pb2+ and F−. The N S-CQDs were selective towards Pb2+. At the same time, the N, S-CQDs + Pb2+ system exhibited selectivity towards F− ions amidst other ions with low detection limits (LODs) of 13.35 nM and 43.17 nM for Pb2+ and F−, respectively. The dynamic quenching mechanism was suggested based on the absorption spectra and lifetime results. Satisfied recoveries of 89.30–116.40% for Pb2+ and 90.22–115.05% for F- (RSD < 5) were obtained in practical samples of wastewater and fish. We believe that the as-synthesized N S-CQDs can effectively serve as reliable, accurate, and swift nanosensor for detecting Pb2+ and F− in environmental samples. [ABSTRACT FROM AUTHOR]

In our research described here, a strong acid oxidizing agent was selected to modify the surface of carbon black (CB) to obtain oxidized carbon black (OCB) particles. These OCB particles were then subjected to an ionic bonding reaction with alkaline amine groups present on the surface of octadecylamine polyoxyethylene ether (AC1830) in the form of a paste, resulting in the production of polyether amine-modified oxidized carbon black particles (A-CB). FTIR confirmed the successful production of the A-CB particles. The PVA composite films were prepared using the casting method with varying amounts of A-CB as filler and PVA as the matrix. The films were then analyzed using tensile, scanning electron microscopy, dynamic thermo-mechanical analysis, DSC, and water absorption testing. The results showed that the tensile strength was highest at 3% A-CB, reaching 154.85 MPa. A-CB was well dispersed in PVA at low contents (1% and 3%). The loss modulus, energy storage modulus, crystallinity, and crystallization rate of the A-CB/PVA films improved compared to PVA films. Additionally, the issue of excessive water absorption in A-CB/PVA has been improved. [ABSTRACT FROM AUTHOR]

Using first principles calculations, the hydrogen storage, mechanical, dynamic, thermodynamic, electronic and optical properties of YCrH 3 (Y = Ca, Sr, Ba) materials are studied for the first time. The lattice constants of CaCrH 3 , SrCrH 3 and BaCrH 3 are 3.70, 3.88 and 4.07 Å, respectively. Exploration of the mechanical properties shows that both CaCrH 3 and BaCrH 3 are brittle, whereas SrCrH 3 is ductile. In addition, all compounds are metallic, thus facilitating efficient charge transfer during hydrogen storage and release. According to the Bader partial net charges, the charge transfer in the YCrH 3 materials is analyzed. The electron density distributions show that the CaCrH 3 hydride contains ionic and covalent bonds, whereas SrCrH 3 and BaCrH 3 are ionic hydrides. Studies of optical properties reveal that CaCrH 3 has the largest static refractive index and dielectric constant. Notably, all the studied hydrides exhibit dynamic, thermodynamic and mechanical stability. The gravimetric hydrogen storage capacities are 3.08, 2.08 and 1.55 wt% for CaCrH 3 , SrCrH 3 and BaCrH 3 , respectively. These investigations provide an important theoretical basis for further exploring the application of hydride materials in the field of hydrogen storage. [ABSTRACT FROM AUTHOR]

Molten salt synthesis (MSS) represents an emerging green and environmentally friendly approach for engineering the structural and phase characteristics of multifunctional materials. In this study, we report the rapid synthesis of cobalt (Co)-based electrodes through MSS under 15 min with high yield. Our findings reveal that the selection of salt precursor significantly influences the crystal phase and morphology of the Co-based electrodes as well as the electrochemical properties. Hydroxide-based salts yielded layered NaxCoO2 with a thin hexagonal morphology, while nitrate-based salts resulted in spinel phase Co3O4 with octahedral structures. Our proposed mechanism highlights the critical role of ionic bonding in these phenomena. The electrochemical evaluation demonstrates that the layered NaxCoO2 electrodes exhibit a specific capacitance of 59 F g−1 (47.2 C g−1) at 1 A g−1 and excellent long-term capacity retention. On the other hand, spinel Co3O4 electrodes, when employed as oxygen evolution reaction (OER) catalysts, exhibit an overpotential of 341 mV to drive a current density of 10 mA cm−2, which is comparable to Co3O4 prepared using other methods that required a significant amount of synthesis time. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT)-1/2 is an efficient bandgap rectification method for DFT under local density approximation (LDA) or generalized gradient approximation. It was suggested that non-self-consistent DFT-1/2 should be used for highly ionic insulators like LiF, whereas self-consistent DFT-1/2 should still be used for other compounds. Nevertheless, there is no quantitative criterion prescribed for which implementation should work for an arbitrary insulator, which leads to severe ambiguity in this method. In this work, we analyze the impact of self-consistency in DFT-1/2 and shell DFT-1/2 calculations in insulators or semiconductors with ionic bonds, covalent bonds, and intermediate cases and show that self-consistency is required even for highly ionic insulators for globally better electronic structure details. The self-energy correction renders electrons more localized around the anions in self-consistent LDA-1/2. The well-known delocalization error of LDA is rectified, but with strong overcorrection, due to the presence of additional self-energy potential. However, in non-self-consistent LDA-1/2 calculations, the electron wave functions indicate that such localization is much more severe and beyond a reasonable range because the strong Coulomb repulsion is not counted in the Hamiltonian. Another common drawback of non-self-consistent LDA-1/2 is that the ionicity of the bonding gets substantially enhanced, and the bandgap can be enormously high in mixed ionic-covalent compounds like TiO2. [ABSTRACT FROM AUTHOR]

To improve the performance of the third-order density-functional tight-binding method (DFTB3) for non-covalent interactions involving organic and biological molecules, a chemical-potential equalization (CPE) approach was introduced [J. Phys. Chem. A, 116, 9131 (2012)] and parameterized for the H, C, N, O, and S chemical elements [J. Chem. Phys., 143, 084123 (2015)]. Based largely on equilibrium structures, the parameterized DFTB3/CPE models were shown to exhibit improvements in molecular polarizabilities and intermolecular interactions. With more extensive analyses, however, we observe here that the available DFTB3/CPE models have two critical limitations: (1) they lead to sharply varying potential energy surfaces, thus causing numerical instability in molecular dynamics (MD) simulations, and (2) they lead to spurious interactions at short distances for some dimer complexes. These shortcomings are attributed to the employed screening functions and the overfitting of CPE parameters. In this work, we introduce a new strategy to simplify the parameterization procedure and significantly reduce free parameters down to four global (i.e., independent of element type) ones. With this strategy, two new models, DFTB3/CPE(r) and DFTB3/CPE(r†) are parameterized. The new models lead to smooth potential energy surfaces, stable MD simulations, and alleviate the spurious interactions at short distances, thus representing consistent improvements for both neutral and ionic hydrogen bonds. [ABSTRACT FROM AUTHOR]

Potato starch can improve the 3D printability of surimi, but the molecular mechanism was not clear. The surimi from golden pompano was the research object and extracted myofibrillar protein from the surimi. The blend system was prepared with myofibrillar protein and potato starch and determined the rheological properties, microstructure, and intermolecular force. The 3D printing effect of surimi was evaluated. The fundamental reason why potato starch improved the 3D printability of surimi was analyzed. Results showed that the content of ionic bonds and hydrophobic interaction between protein molecules decreased, while the content of hydrogen bonds and disulfide covalent bonds increased, which promoted the conformational changes of amino acids in the side chain of protein molecules. When the mass ratio of myofibrillar protein to potato starch was 6:4, the link strength between rheological units of the blend system was 8 877. 2 Pa·s1 / z and the apparent viscosity was 2 818 Pa·s. At this time, the 3D printing effect of surimi was the best, and the printing accuracy and stability were 99. 6% and 98. 12% respectively. This study provided theoretical support for the formulation design and development of 3D-printed surimi products and had far-reaching practical significance for the wide application of 3D printing in the food industry. [ABSTRACT FROM AUTHOR]

Herein we report a square-like D4h H©K4H4− anion with one planar tetracoordinate hydrogen (ptH) center, which is the global minimum (GM) structure and possesses good dynamic stability. The planar structure of the system is preserved by four peripheral K–H–K three-center two-electron (3c-2e) σ bonds together with one 5c-2e σ bond over the HK4 core. The multicenter ionic bonds dominate the stability of ptH, while the contribution of qualitative σ aromaticity is extremely limited. [ABSTRACT FROM AUTHOR]

Photosynthesis of hydrogen peroxide (H2O2) is regarded as an economically efficient and environmentally friendly synthesis method. However, the scalability of photocatalytic H2O2 production (PHP) is hindered by the sluggish reaction kinetics and rapid recombination of photogenerated charge carriers. In this study, an organic amine‐constrained ions intercalated carbon nitride/CdSe‐diethylenetriamine (K+/I−‐CN/CdSe‐D) S‐scheme heterojunction is synthesized using an organic–inorganic hybrid approach and employed for PHP for the first time. The optimization of the heterojunction interface by I− and K+ ions contributed to enhanced light absorption capabilities and reduced interlayer charge transfer distance. Concurrently, the synergy of C─Se bonds at interface effectively modulated the electron transfer pathways. The coordination environment and charge transfer mechanism are thoroughly investigated by extended X‐ray absorption fine structure and in situ irradiated X‐ray photoelectron spectroscopy. The H2O2 production rate of 40%K+/I−‐CN/CdSe‐D reached 2240.23 µmol h−1 g−1 in pure water. This study highlights the significance of dual tuning of interface chemical bonds and ionic intercalation as an effective strategy for enhancing the photocatalytic H2O2 , paving the way for further advancements in PHP technology. [ABSTRACT FROM AUTHOR]

This study investigates the structural stability and electronic properties of α‐MX nanothreads and β‐MX nanosheets (M=Au, Ag; X=S, Se) using density functional theory. Our findings confirm the thermal and dynamic stability of all nanostructures, with β‐MX phases being more stable than α‐MX, albeit with minimal energy differences between the two phases. Electron localization analysis reveals predominantly ionic bonding character between M (Ag and Au) and X (S and Se) atoms. All the phase exhibits metallophilic interactions (Argentophilic and Aurophilic), with α‐MX nanothreads demonstrating a higher level of interaction compared to β‐MX nanosheets, attributed to the curvature inherent in the nanothreads. Significantly, these interactions are effectively small and do not compromise the relative stability between the α‐MX and β‐MX phases. Additionally, both α‐MX and β‐MX structures exhibit characteristics of indirect bandgap semiconductor behaviour. The band gap values do not significantly differ between α‐MX and β‐MX phases. Fermi analysis reveals that α‐MX phases exhibit small effective electron masses and large hole mobility along the uniaxial direction. These findings suggest promising prospects for α‐MX nanothreads as 1D semiconductors in nano‐electronics and nano‐optoelectronics applications in the future. [ABSTRACT FROM AUTHOR]

In this work, a new type of complex was constructed by coordinating quercetin (QC) with cerium (Ce) ions. This complex was introduced into perfluorosulfonic acid resin (PFSA) to fabricate a proton exchange membrane. The coordination process prevented the formation of ion cross-links between cerium and sulfonic acid groups in PFSA, thereby keeping proton conductivity and fuel cell performance of membrane samples at a high level. Due to the insolubility of quercetin in water, its coordination with cerium minimized cerium migration, providing long-lasting resistance to free radicals. The effects of additives on PFSA membrane properties were investigated by measuring IEC, water uptake, swelling ratio, and proton conductivity. Fenton degradation experiments and membrane electrode assembly performance tests was conducted simultaneously. The results demonstrated that compared to the addition of quercetin or cerium alone, the use of QC-Ce increased the proton conductivity by 23.70% after 24-h Fenton degradation and lowered fluoride release by 58.29%. Meanwhile, the PFSA/QC-Ce composite membrane samples maintained an open circuit voltage of 0.935 V and a maximum power density of 668.15 mW cm−2 after 96 h of open circuit voltage hold testing. • Combining organic antioxidant and cerium ions through coordination. • Reduces mainly ionic bonds and maintains the membrane performance. • Limits the migration of cerium for long-term free radical scavenging. • Organic antioxidant and cerium ions synergistically eliminate free radicals. [ABSTRACT FROM AUTHOR]