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A dual-channel material of {[(CH3)2NH2][Yb3(BDCP)2(H2O)3]·2DMF·3H2O}n (NUC-58) has been generated from the combination of wave-like [Yb2(CO2)6(H2O)2]n chains and [Yb(CO2)4(H2O)] units with the aid of 2,6-bis(2,4-dicarboxylphenyl)-4-(4- carboxylphenyl)pyridine, which has excellent physical and chemical properties including a larger specific surface area, high porosity, water resistance and thermal stability. NUC-58 is a rarely reported microporous MOFs with solvent-free dual channels. Thanks to its coexistence of Lewis acid–base sites including rich hexa/hepta-coordinated Yb3+ ions, C = O groups from μ1−η1:η1 CO2−, and Npyridine atoms, NUC-58 displays highly catalytic activity on the cycloaddition reaction of epoxides and CO2 into related cyclic carbonates under mild solvent-free reaction conditions. In addition, NUC-58 could be used as a fast, sensitive and highly efficiency sensor for Cu2+ detection in aqueous solution. Therefore, the work shows that microporous MOFs assembled from pyridine-containing polycarboxylic acid ligands and rare earth ions can serve as excellent catalytic and luminescent materials. A highly robust ytterbium (III)-organic framework of {[(CH3)2NH2]2[Yb3 (BDCP)2(NO3)(OH2)3]·2DMF·3H2O}n (NUC-58) for efficiently catalyzing the chemical fixation of CO2. [ABSTRACT FROM AUTHOR]

In recent years, a significant number of metal-based catalysts were synthesized for the CO 2 cycloaddition reaction. However, the leaking of active metal elements resulted in various environmental issues. To prevent the loss of active components and enhance the catalyst lifespan, a confined catalysis strategy involving a multi-functionalized core-shell catalyst with Lewis acid-base (B/Br) and hydrogen bond donor (-OH) was designed. It was noteworthy that B-mSiO 2 @MCM-IMOH featured multifunctional catalytic active sites, including Lewis acid-base (B/Br) and hydrogen bond donor (-OH), and the cooperative effect of B, Br and -OH significantly improved the catalytic activity. Therefore, B-mSiO 2 @MCM-IMOH demonstrated outstanding catalytic performance for the CO 2 cycloaddition reaction. In addition, the core-shell molecular sieve, serving as a confined catalytic carrier, effectively enhanced the stability and recyclability of the catalyst. Utilizing DFT calculations, a cooperative catalytic mechanism was proposed involving Lewis acid-base (B/Br) and hydrogen bond donor (-OH). The synergistic interaction between B/Br and -OH markedly reduced the energy barrier for the ring-opening of propylene oxide from 58.6 kcal·mol−1 to 21.5 kcal·mol−1, thus facilitating the PO-CO 2 cycloaddition reaction. [Display omitted] • The coexistence of B/Br and -OH in the core-shell catalyst was confirmed. • A confined catalysis strategy enhances the recyclability of the catalyst. • Lewis acid-base (B/Br) and HBD group (-OH) have an excellent synergistic effect. • A synergistic catalysis mechanism was confirmed by theoretical calculations. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), constructed from organic ligands that are rich in conjugated π bonds, have been gaining significant attention for gas sensing. This paper reports the synthesis of Nb-H 2 BIPA-TC, an octahedral MOF, starting from niobium as the metal centre and benzoimidephenanthroline tetracarboxylic acid (H 4 BIPA-TC) as the ligand. The Nb-H 2 BIPA-TC-MOF was grown under light irradiation on the surface of a lithium niobate waveguide substrate and assessed for its ability to sense acidic and basic gases. The Nb-H 2 BIPA-TC-MOF formed an octahedral crystal structure after being grown for only 20 min. The obtained film was optically transparent and featured low light attenuation (< 1.28 dB mm−1). Owing to the Lewis acid-base nature of the Nb-H 2 BIPA-TC-MOF, the designed sensor exhibited a specific 'turn on-off' sensing response to H 2 S, SO 2 , and ethylenediamine (EDA) gases. The host-guest interaction between the gas-sensitive Nb-H 2 BIPA-TC -MOF and different analyte gases induced different degrees of 'on-off' switching in its refractive index. The designed MOF showed a significant and reproducible 'turn on-off' response to H 2 S and EDA gases in the 0.1–100 ppm concentration range. The designed MOF responded to these two gases for at least 28 days with a 10–23 % reduction in the sensing response per 7 days. Owing to its low immunity to relative humidity, the designed MOF can be employed under low humidity conditions for the detection of H 2 S/SO 2 and EDA. • An octahedral Nb-H 2 BIPA-TC-MOF was fabricated using UV light irradiation approach. • The designed Nb-MOF exhibited a specific 'turn on-off' response to H 2 S/SO 2 and EDA. • The host-guest interaction induced different degrees of the 'on-off' switch in RI. • The designed Nb-H 2 BIPA-TC-MOF is reproduced and suite for low humidity condition. [ABSTRACT FROM AUTHOR]

Defect passivation has been recognized as an effective strategy to improve efficiency and stability of perovskite solar cells (PSCs). In this work, in‐depth theoretical calculations and experimental characterizations reveal the dual‐site synergistic passivation of 1H‐benzimidazole (BIZ), and the conjugated structure of the benzene ring tends to increase the interaction between BIZ and perovskite. High‐quality perovskite films are thus achieved, with increased grain size, reduced defect density, and suppressed ion migration. Simultaneously, the reduced work function and optimized band alignment promote carrier transport, reducing nonradiative recombination, and loss of open‐circuit voltages, as well as fill factor. Consequently, the target PSC devices achieve a champion power conversion efficiency (PCE) of 24.59%, and 20.49% for perovskite solar module (a designated area of 27.5 cm2). The unencapsulated PSC maintains 91.49% of original PCE after storing in air with an average relative humidity of 40% for 2400 h. Moreover, the device exhibits remarkable the long‐term operational stability, maintaining 90.47% of initial PCE after continuously operating at the maximum power point for 1000 h. This study not only provides insights into the synergistic passivation of BIZ but also provides a strategy for the application of BIZ derivatives in the photovoltaic field. [ABSTRACT FROM AUTHOR]

All‐inorganic cesium‐lead‐iodide (CsPbI3Br3−x (2 < x < 3)) perovskite presents preeminent photovoltaic performance and chemical stability. Unfortunately, this kind of material suffers from phase transition to a nonperovskite phase under oxidative chemical stresses. Herein, the introduction of a low concentration of Lewis acid–base adducts (LABAs) is reported to synergistically reduce defect density, optimize interfacial energy alignment, and improve device stability of CsPbI2.75Br0.24Cl0.01 (CsPbTh3) solar cells. Both theoretical simulations and experimental measurements reveal that the noncoordinating anions, PF6−, as a Lewis base can more effectively bind with undercoordinated Pb2+ to passivate iodide vacancy defects than the BF4− and absorbed I−, and thus the point defects are well suppressed. In addition, N‐propyl‐methyl piperidinium (NPMP+) is selected to assemble with PF6− in CsPbTh3 film. The NPMP+ can regulate the crystal growth and finally homogenize the grain size and decrease the trap density. Consequently, the LABAs strategy can improve the power conversion efficiency of CsPbTh3 solar cells to 19.02% under 1‐sun illumination (100 mW cm−2). Fortunately, the NPMP+ and PF6−‐treated CsPbTh3 film shows great phase stability after storage in ambient air for 250 days, and the power conversion efficiency of corresponding solar cells is almost 76% of the initial value after 60 days aging under ambient conditions. [ABSTRACT FROM AUTHOR]

The chemical transformation of CO2 and epoxides into cyclic carbonates has been receiving much attention and is one of the successful examples for CO2 utilization as carbon resource. Many catalysts containing halide anions have been explored and exhibit excellent catalytic activity. However, halogen salt is generally toxic and corrosive to reactors. From a green chemistry perspective, it is more attractive to develop a halogen-free catalyst with excellent performance. Herein, a review of recent research progress of halogen-free catalysts in the cycloaddition of CO2 and epoxide is presented. According to previous experimental and theoretical works, two possible strategies for achieving the halogen-free process were summarized. The relationship between catalytic activity and catalyst structure, the mechanism of CO2 activation should be both studied deeply combined with experimental results and DFT calculation, which can guide the design of new catalysts and realize halogen-free process under mild reaction conditions.

Introduction: Hypervirulent Klebsiella pneumoniae (hvKp) and carbapenem-resistant K. pneumoniae (CR-Kp) are rapidly emerging as opportunistic pathogens that have a global impact leading to a significant increase in mortality rates among clinical patients. Anti-virulence strategies that target bacterial behavior, such as adhesion and biofilm formation, have been proposed as alternatives to biocidal antibiotic treatments to reduce the rapid emergence of bacterial resistance. The main objective of this study was to examine the efficacy of fatty acid-enriched extract (AWME3) derived from the fat of Black Soldier Fly larvae ( Hermetia illucens ) in fighting against biofilms of multi-drug resistant (MDR) and highly virulent Klebsiella pneumoniae (hvKp) pathogens. Additionally, the study also aimed to investigate the potential mechanisms underlying this effect., Methods: Crystal violet (CV) and ethidium bromide (EtBr) assays show how AWME3 affects the formation of mixed and mature biofilms by the KP ATCC BAA-2473, KPi1627, and KPM9 strains. AWME3 has shown exceptional efficacy in combating the hypermucoviscosity (HMV) virulent factors of KPi1627 and KPM9 strains when tested using the string assay. The rudimentary motility of MDR KPM9 and KP ATCC BAA-2473 strains was detected through swimming, swarming, and twitching assays. The cell wall membrane disturbances induced by AWME3 were detected by light and scanning electron microscopy and further validated by an increase in the bacterial cell wall permeability and Lewis acid-base/van der Waals characteristics of K. pneumoniae strains tested by MATS (microbial adhesion to solvents) method., Results: After being exposed to 0.5 MIC (0.125 mg/ml) of AWME3, a significant reduction in the rudimentary motility of MDR KPM9 and KP ATCC BAA-2473 strains, whereas the treated bacterial strains exhibited motility between 4.23 ± 0.25 and 4.47 ± 0.25 mm, while the non-treated control groups showed significantly higher motility ranging from 8.5 ± 0.5 to 10.5 ± 0.5 mm., Conclusion: In conclusion, this study demonstrates the exceptional capability of the natural AWME3 extract enriched with a unique combination of fatty acids to effectively eliminate the biofilms formed by the highly drug-resistant and highly virulent K. pneumoniae (hvKp) pathogens. Our results highlight the opportunity to control and minimize the rapid emergence of bacterial resistance through the treatment using AWME3 of biofilm-associated infections caused by hvKp and CRKp pathogens., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Mohamed, Marusich, Divashuk and Leonov.)

• Allantoin with carbonyl and amino groups can systematically passivated defects. • The formed hydrogen bonds can suppress the deprotonation behaviors of FAI/MAI. • The monomers can be adequately attracted and utilized to reduce materials losses. • Perovskite components can be well anchored to avoid degradations and Pb leakage. • Crystal quality and long-term stability of perovskites were greatly improved. CsFAMA-based perovskite solar cells (PSCs) have become promising photovoltaic materials due to their excellent photovoltaic properties. However, the inherent instability of perovskite severely hinders its commercialization, since the typical ionic nature of perovskite can cause the ionic migration and volatilization of organic components. Herein, allantoin molecules with multiple alternating carbonyl (C = O) and amino (–NH 2 or –NH–) groups were introduced as a multidentate additive to synergistically anchor the perovskite components and passivate the defects, resulting in non-radiative recombination and ion migration being not susceptible to occur. Due to the favorable attraction ability of allantoin to the perovskite precursor monomers and the formation of hydrogen bonds between FAI/MAI and allantoin, the crystal quality of perovskite was significantly improved and the bulk/interface defects were effectively eliminated. Specifically, the interaction between allantoin and FA+/MA+ can suppress their deprotonations and prevent the volatilization of organic cations from the initial precursor solutions, drastically reducing the wastage of precursor materials. Consequently, the modified devices demonstrated a prominent elevation of performance with a higher efficiency of 21.49 %, which was better than that of control (19.67 %). Moreover, the modified perovskite films also demonstrated prominent stability under the continuous illumination and moisture aging owing to the reduction of trap defects. The allantoin additives also greatly enhanced the hydrophobicity of perovskite, and the modified device maintained 90 % of its initial efficiency for 1680 h at 10–20 % relative humidity without encapsulation. [ABSTRACT FROM AUTHOR]

Boron is the archetypal Lewis acid, and therefore it is only natural that it prefers to bind nitrogen, its usual Lewis base counterpart. To challenge this assumption, we present a computationally designed bicyclopentane molecule akin to [1.1.1]propellane, but with pyramidal B and N inner atoms bonded by an "inverted" dative bond. Unexpectedly, the dimer of this system prefers to interact via an atypical boron-boron bond over the supposedly obvious boron-nitrogen bond. A molecular orbital analysis shows that the boron in this peculiar entity acts both as an electron donor and an electron acceptor, making the dimerization an amphoteric-amphoteric interaction process., (© 2023 Wiley-VCH GmbH.)

Abstract Recently, numerous efforts have been reported on improving the properties of perovskite absorber, which has a direct and significant influence on the photovoltaic performance of solar cells. In this paper, lead acetate was introduced into stoichiometric lewis acid-base perovskite precursor to prepare high-quality methylammonium lead halide (MAPbI 3) perovskite films. The trace lead acetate can facilitate the perovskite crystallization and induce grain size growth. After introducing lead acetate, the perovskite films show higher photoluminescence intensity and longer carrier lifetime due to less traps and defects, which is attributed to the improved film properties. The impedance spectroscopy measurements reveal that the lead acetate can decrease the series resistance and recombination resistance in the perovskite solar cells. As a result, the perovskite solar cells with lead acetate achieve an improved average efficiency of 18.06% (18.86% of best efficiency) compared with 16.87% of average efficiency of the control samples without lead acetate, while the hysteresis behavior is also significantly suppressed with the lead acetate. Graphical abstract Image 1 Highlights • The lead acetate was introduced into the stoichiometric lewis acid-base precursor to prepare high-quality perovskite films. • The lead acetate can improve the perovskite crystallization and passivate the traps. • The device efficiency improved significantly with suppressive hysteresis behavior by introducing lead acetate. [ABSTRACT FROM AUTHOR]

[Ru(benzene)(en)Cl] + (en = ethylenediamine) is a very active anticancer drug like cisplatin. It has been shown that upon coordination to metal in half sandwich ruthenium complex the benzene ring becomes electron deficient. A library of Lewis bases: Tetrahydrofuran (THF), Acetonitrile (MeCN), Diethyl ether (Et 2 O), Water (H 2 O), Trimethylamine (Me 3 N), Ammonia (NH 3 ), Pyridine (Py), Benzene (Bz), Furan, Adenine, Carbon monoxide (CO), Thiophene and Phosphine (PH 3 ) are considered to study the Lewis acid character of the metal bound benzene. The binding energies of the bases are calculated at M06-2X/LanL2DZ(Ru), 6-31+G ∗ (C, H, N, O, P, S, Cl) level using Density Functional Theory (DFT) and the values are compared with free benzene. A conformational sampling analysis is carried out to get the most stable supermolecul. It is found that the binding energy is significantly higher in case of coordinated benzene in [Ru(benzene)(en)Cl] + (e.g., interaction energy of Py is −5.56 Kcal mol −1 more in [Ru(benzene)(en)Cl] + than that of free benzene). An Energy Decomposition Analysis shows that for the coordinated benzene the stability of the acid-base adduct comes from the combination of electrostatic and dispersion term. From the Quantum Theory of Atoms in Molecules (QTAIM) a cage critical point (CCP) is found in between the donor atom of base and centroid of the benzene ring. The values of electron density of the bond critical point (BCP) in the supermolecule are higher in coordinated benzene than that of the free one. Moreover, a change in the electron density and its Laplacian of the ring critical point (RCP) and bond critical points of the benzene ring in metal bound and free state have been observed. Nucleus Independent Chemical Shift (NICS) calculations also show change in the values of NICS(0) and NICS(1) upon interaction of benzene with Lewis base. An interesting experimental observation of the formation of substituted cyclohexadienyl complex of ruthenium(II) from the reaction of [Ru(benzene)Cl 2 ] 2 with nucleophilic reagents hydride, hydroxide and cyanide have been justified from DFT calculations. Thermochemical parameters; enthalpy (ΔH) and free energy (ΔG) of the reactions suggest the adduct formation follows the order: H −  > OH −  > CN − . This is because of the electron deficient nature of coordinated benzene and hence the nucleophilic reagent undergoes addition reaction. Global and local reactivity parameters such as chemical potential, hardness, electrophilicity index and Fukui function are calculated to understand the electronic properties. [ABSTRACT FROM AUTHOR]

A computational study at several DFT levels of theory was performed for the mono- and diphosphaalkenyl germylene systems in order to understand the Lewis acid-base behaviour of these species towards a few electron-donor systems like tetrahydrofuran, diethyl ether and 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene or/and electron-acceptor ones, as PdCl 2 and PtCl 2 . The ability of these species to concurrently act as a Lewis acid and base was confirmed by the experimental study (synthesis and structural characterization of a new platinum(diphosphaalkenyl)germylene) that aimed to emphasize the theoretical data obtained. [ABSTRACT FROM AUTHOR]

The crystal and molecular structure of 2-(diphenylphosphano)phenyl benzoate borane adduct are reported. The title compound crystallizes from a petroleum ether/ethyl acetate mixture in the triclinic space group P with two molecules in the unit cell. The unit cell parameters are: a = 8.67(1) Å, b = 9.202(1) Å, c = 14.224(2) Å; α = 72.600(7)°, β = 73.577(7)°, γ = 84.349(7)° and V = 1039.5(2) Å3. Bond lengths and angles are typical for this phosphane borane adduct.

Membrane fouling and the trade-off between membrane permeability and selectivity restrict the potential applications of membrane filtration for water treatment. ZIF-8 was found having great permeability and antibiofouling performance, but with issue on particle aggregation makes it difficult to achieve high ZIFs loading and fabricate a defect-free molecular sieving membrane in previous research. In this study, we formed a scalable antibiofouling surface with improved permeability and fouling resistance on a PEI-ZIF-PAA membrane using a layer-by-layer assembly technique. The synergistic effects of being sandwiched between two different polyelectrolyte layers with opposite charges endowed the ZIF nanoparticles with improved stability and scalability for membrane modification. The PEI-ZIF-PAA membrane exhibited a satisfactory water flux of 120.78 LMH, which was 46.97% higher than that of the pristine PES membrane. The normalized water flux loss was serious in the absence of ZIF-8, and the flux increased with the ZIF-8 concentration. Antifouling tests suggested that the PEI-ZIF-PAA membrane possessed good antifouling performance due to the much higher surface hydrophilicity and positive Lewis acid-base interactions with foulants. The HA rejection increased with the ZIF-8 concentration and reached a maximum of 92.1% in the presence of 1.00% (w/v) ZIF-8. The membrane regeneration was tested under physical and chemical cleaning with flux recovery rates of about 85% and 95%. XDLVO analysis showed that the total interaction energy between HA and the PEI-ZIF-8-PAA membrane was 26.45 mJ/m2, and the superior antifouling performance was mainly attributed to Lewis acid-base interactions. This study indicates that ZIF-8 nanocrystals are promising materials for fabricating novel membranes for sewage treatment. [Display omitted] • PEI-ZIF-PAA membrane was synthetized using layer-by-layer assembly technique. • Sandwich ZIF-8 nanoparticles were densely and uniformly dispersed. • The PEI-ZIF-PAA membrane has high HA rejection efficiency and flux recovery rates. • Antifouling capacity is due to strong repulsion force and improved hydrophilicity. [ABSTRACT FROM AUTHOR]

• The acidic hysrothermal self-assembly of H 5 BDCP and lutetium oxide generated a microporous dual-channel material. • OIM-1 has the excellent physicochemical properties of solvent-free dual channels, bigger specific surface area, high porosity and thermal stability. • Acitivated OIM-1 , as a heterogenous catalyst, can efficiently catalyze the cycloaddition reaction of CO 2 with epoxides under mild conditions. Herein, a highly robust dual-channel material of {[(CH 3) 2 NH 2 ] 2 [Lu 3 (BDCP) 2 (NO 3)(OH 2) 3 ]·4DMF·2H 2 O} n (OIM-1) built on the combination of wave-like [Lu 2 (CO 2) 6 (OH 2) 2 ] n chains and [Lu(CO 2) 4 (NO 3)(OH 2)] units was synthesized from the structure-oriented ligand of 2,6-bis(2,4-dicarboxylphenyl)-4-(4-carboxylphenyl)pyridine (H 5 BDCP) and lutetium oxide under solvothermal condition. Performance characterizations exhibit that OIM-1 has the excellent physicochemical properties of solvent-free dual channels, bigger specific surface area, high porosity and thermal stability. Because of coexisted Lewis acid-base sites including rich hexa/hepta-coordinated Lu3+ ions, N=O and C=O groups from μ 1 - η 1: η 1 NO3− and CO2−, and N pyridine atoms, acitivated OIM-1 , as a heterogenous catalyst, displays the high catalytic performance on the cycloaddition reaction of CO 2 with epoxides into cyclic carbonates under the mild solvent-free reaction conditions of 1 atm and 60 °C within 6 h. [Display omitted] A microporous thulium-organic framework of {[CH 3) 2 NH 2 ] 2 [Lu 3 (BDCP) 2 (NO 3)(OH 2) 3 ]·4DMF·2H 2 O} n (OIM-1) displays highly catalytic activity on the cycloaddition reaction of epoxides with CO 2 and Knoevenagel condensation reaction. [ABSTRACT FROM AUTHOR]

A straightforward protocol was developed to detect the prostate cancer biomarker citrate, using boronic acid as a new recognition unit for exploring the sequence of a Lewis acid-base reaction, Spiro-lactam ring opening, followed by FRET sensing strategies. The probe was evolved from rhodamine-indole extended phenylboronic acid (RIB), which reacted with citrate to produce enhanced red fluorescence in the mitochondria of cell lines (in vitro), allowing the in vivo tracking of citrate. The emission changes were monitored in terms of the endogenous (in situ) citrate concentrations to distinguish normal to prostate cancer mice and their dissected prostate tissues. The practicability of the RIB probe was assessed using urine samples, and paper-made sensor strips as a biochemical reagent to detect the citrate and help diagnose prostate cancer in the early stages. [Display omitted] • Rhodamine-red emissive probe was developed for tracking prostate cancer biomarker citrate. • Exploring a Lewis acid-base reaction, Spiro-lactam ring opening, and FRET mechanisms. • Mitochondria targeting ability, insitu citrate concentration were monitored in cell lines and mice, respectively. • The practicability was investigated using urine, fabrication of paper sensor strips. [ABSTRACT FROM AUTHOR]

A new series of solvatochromic mononuclear mixed ligand chelates with the general formula: Cu(AcBL)(L)X; where AcBL = 2-acetylbutyrolactonate, L = N,N,N′,N′-tetramethylethylenediamine (Me 4 en), N,N,N′,N′-tetramethylpropylene diamine (Me 4 pn), 1,10-phenanthroline (Phen) or 2,2′-bipyridyl (Bipy) and X = ClO 4 − , NO 3 − or Br − have been synthesized and characterized by the analytical and spectral methods, as well as magnetic and molar conductance measurements. The d–d absorption bands of Me 4 en-chelates as Nujol mulls or weak donor solvents solutions revealed square-planar, distorted octahedral and/or distorted trigonal bipyramid geometries for the perchlorate, nitrate and bromide chelates, respectively. However, an octahedral structure is identified for chelates in strong donor solvents. Perchlorate chelates show a remarkable color change from violet to green as the Lewis basicity of the donor solvent increases, whereas bromide chelates are mainly affected by the Lewis acidity of solvent. Specific and non-specific interactions of solvent molecules with the chelates were investigated on the basis of unified solvation model. Structural parameters of the free ligands and their Cu(II)-chelates have been calculated on the basis of semiempirical PM3 level and correlated with the experimental data. [ABSTRACT FROM AUTHOR]

A new pentafunctional N 3 O 2 Schiff base, H 2 L ligand, and its metal chelates with Cu(II), Ni(II), Co(II), VO(IV), Zn(II), Cd(II), Ce(III), Cr(III), Fe(III) and UO 2 (VI) have been synthesized and characterized by elemental analysis, spectral, molar conductance, magnetic and thermal gravimetric studies. The results showed that the complexes have octahedral geometry except UO 2 complex which has pentagonal bipyramidal arrangement. The TGA analyses suggest high stability for most complexes followed by thermal decomposition in different steps. The kinetic and thermodynamic parameters for decomposition steps of metal complexes thermograms have been calculated. Molecular orbital calculations were performed for the ligand and its metal complexes by means of hyperchem 7.52 program on the bases of semiempirical PM3 level and the results were correlated with the experimental data. The antimicrobial activity of the synthesized compounds were tested in vitro against some Gram-positive and Gram-negative bacteria; yeast and fungus strains and the results were discussed in terms of extended Lewis acid–base interactions. [ABSTRACT FROM AUTHOR]

The crystal and molecular structure of 2-(diphenylphosphano)phenyl benzoate3borane adduct are reported. The title compound crystallizes from a petroleum ether/ethyl3acetate mixture in the triclinic space group P1 with two molecules in the unit cell. The unit3cell parameters are: a = 8.67(1) Å, b = 9.202(1) Å, c = 14.224(2) Å; a = 72.600(7)°, β = 73.577(7)°, γ = 84.349(7)° and V = 1039.5(2) ų. Bond lengths and angles are typical for this phosphane borane adduct. [ABSTRACT FROM AUTHOR]

Amine-functionalized bimetallic zeolitic imidazolate framework-8 (Co/Zn-ZIF-A) with 3-amino-1,2,4-triazole (Atz) was synthesized by a post-synthetic modification and utilized as a heterogeneous catalyst for the synthesis of cyclic carbonates from CO 2 and epoxides. Different amine contents in Co/Zn-ZIF-A materials were controlled by adjusting the ligand exchange reaction time of the of 2-mIM with Atz. Co/Zn-ZIF-A-24 h with the highest amine contents (32% of Atz) achieved an excellent result of 99% conversion of epichlorohydrin with high selectivity of > 99% after 24 h without co-catalyst and solvent under mild conditions (80 oC, 1 bar CO 2). The enhanced catalytic activity is attributed to the acid-base synergistic effect by the combination of bimetallic systems consisting of Zn and Co as Lewis acid sites and the abundant Lewis bases sites of -NH 2 , -NH groups from Atz ligand. A kinetic study of the cycloaddition reaction over Co/Zn-ZIF-A-24 h confirmed an approximately first-order dependence on the epichlorohydrin concentration and CO 2 pressure with an activation energy of approximately 39.5 kJ mol-1. Co/Zn-ZIF-A-24 h catalyst showed good reusability with no obvious loss in catalytic activity during five recycling runs and its structural stability was also confirmed. A plausible reaction mechanism of Co/Zn-ZIF-A catalyst for CO 2 -epoxide cycloaddition was proposed. [Display omitted] • Amine-functionalized bimetallic Co/Zn-ZIFs (Co/Zn-ZIF-A) were synthesized by post-synthetic modification. • Co/Zn-ZIF-A was found to be catalytically efficient for CO 2 /epoxide coupling reaction under mild conditions. • Synergistic effect of amine groups and bimetallic systems on accelerating the epoxide ring-opening. • Co/Zn-ZIF-A demonstrates excellent catalytic activity without solvent and any co-catalyst. [ABSTRACT FROM AUTHOR]

The reactivity descriptors like electronegativity, hardness, and electrophilicity, formulated on conceptual density functional theory can explain chemical reactivity of various acids and bases, oxidants and reductants as well as electrophiles and nucleophiles through associated structure-stability diagrams. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Three Lewis acid–base adducts [(PhBO)3·2hmt] (1), [(PhBO)3–hmt–(PhBO)3] (2) and [{(F-Ph)BO}3·hmt] (3) (hmt = hexamethylenetetramine) were prepared by the treatment of phenylboronic acid [PhB(OH)2] or 4-fluorophenylboroxine [{(F-Ph)BO}3] with hexamethylenetetramine (hmt) in methanol or acetone. The solid state structures of all the compounds were established by single crystal X-ray diffraction analysis. Crystal structure determination indicates the formation of boroxine ring through ligand-mediated dehydration of arylboronic acids. Triphenylboroxine acts as a bridge between two hmt molecules in 1, whereas hmt plays the role of a bridging ligand between two triphenylboroxine rings in 2. Compound 1 is rare 1:2 adduct of triphenylboroxine and hmt whereas compound 2 and 3 are 1:2 and 1:1 adducts of triphenylboroxine or 4-fluorophenylboroxine and hmt respectively. The lability of the B–N bond in solution was confirmed by NMR spectroscopy as well as by chemical reaction of 1 with [Co(H2O)6](ClO4)2, resulting in the formation of [Co(H2O)6](ClO4)2·(hmt)2·2H2O (4), a boroxine free hydrogen bonded framework structure. [ABSTRACT FROM AUTHOR]

Highlights: [•] The combination of PDADMAC and TC4 enable microencapsulation of dodecane in PMMA. [•] Stabilization of the dodecane–PMMA interface leads to multicore morphology. [•] PDADMAC adsorbs strongly at the TC4 containing PMMA interface. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the influence of surface treatment of glass-ionomer (GIC) on bond strength of resin composite and surface free energies. Specimens were prepared and divided into three groups as follows: without pretreatment (control), phosphoric acid etching, and air-abrasion. Adhesive was applied and resin composite was bonded. For conventional GIC, acid etching or air-abrasion increased bond strength (8.5-8.8 MPa) when compared with controls (4.7 MPa); however, RMGIC resulted in significantly lower bond strengths (10.3-15.8 MPa) than in controls (14.2-20.5 MPa). The value of the γs- component increased when conventional GIC was treated with phosphoric acid or air-abrasion (60.1-60.5 mJ.m-2) when compared with controls (52.8 mJ.m-2). These results indicate that surface treatment of conventional GIC promoted higher bond strength to resin composite and higher Lewis-base components, but decreased bond strength for RMGIC. [ABSTRACT FROM AUTHOR]

Abstract: The available data on main group (Groups 12–18) Lewis acid–base, donor–acceptor, charge-transfer and van der Waals complexes stabilised by matrix isolation techniques are presented, tabulated and evaluated in conjunction with data from complementary gas phase experiments and computational chemistry. [Copyright &y& Elsevier]

Ammonia borane (AB) is the most widely studied hydride for hydrogen storage in addition to being a useful reducing agent. Attempts to synthesize pure AB through simple displacement reactions date back to the 1960s; but have been thwarted by the formation of the diammoniate of diborane (DADB), an ionic byproduct. Based on our recent characterization of the formation mechanism of DADB, we have developed a large-scale synthesis of pure AB by both increasing the basicity of the Lewis base of the borane carrier and using a nonpolar solvent to limit the formation of an intermediate, the ammonia diborane (AaDB). Conditions were optimized for the preparation of pure AB by two displacement reactions, either ammonia with dimethylsulfide borane or ammonia with dimethylaniline borane in toluene at room temperature. These procedures are also suitable for preparation of other amine boranes which had the same problem of forming ionic byproducts during displacement reactions. [ABSTRACT FROM AUTHOR]

Abstract: Optical methods combine the wide availability of molecular indicators with simple and contactless measurements. In this context, indicator-displacement assay is a viable strategy for developing optical chemosensors with synthetic receptors. Such approach may be used to overcome the limits of sensing molecules and to widen the range of detectable compounds. In this paper, it is shown that proper blends of porphyrins and Lewis acid-base indicators can give rise to sensitive units whose properties exceed those of single components. [Copyright &y& Elsevier]

Abstract: Influx of Phosphorus (P) into freshwater ecosystems is the primary cause of eutrophication which has many undesirable effects. Therefore, P discharge limits for effluents from WWTPs is becoming increasingly common, and may be as low as 10 μg/L as P. While precipitation, filtration, membrane processes, Enhanced Biological Phosphorus Removal (EBPR) and Physico-chemical (adsorption based) methods have been successfully used to effect P removal, only adsorption has the potential to recover the P as a usable fertilizer. This benefit will gain importance with time since P is a non-renewable resource and is mined from P-rich rocks. This article provides details of a process where a polymeric anion exchanger is impregnated with iron oxide nanoparticles to effectuate selective P removal from wastewater and its recovery as a solid-phase fertilizer. Three such hybrid materials were studied: HAIX, DOW-HFO, & DOW-HFO-Cu. Each of these materials combines the durability, robustness, and ease-of-use of a polymeric ion-exchanger resin with the high sorption affinity of Hydrated Ferric Oxide (HFO) toward phosphate. Laboratory experiments demonstrate that each of the three materials studies can selectively remove phosphate from the background of competing anions and phosphorus can be recovered as a solid-phase fertilizer upon efficient regeneration of the exchanger and addition of a calcium or magnesium salt in equimolar (Ca/P or Mg/P) ratio. Also, there is no leaching of Fe or Cu from any of these hybrid exchangers. [Copyright &y& Elsevier]

Abstract: The electrostatic beneficiation of coal is based on different tribo-charging characteristics of ash forming minerals and coal particles. In this work the tribo-charging of quartz and coal particles contacted with various metals and polymer materials have been measured and the charge acquisition was examined through surface energy calculations from liquid contact angle data. The contacts angles, before and after tribo-charging of solids, were measured with Krüss tensiometer using Washburn''s equation where the sample holders in tensiometer are specially constructed with tribo-charger materials. The polarity and amount of charge acquired by quartz and carbon powders with metal tribo-chargers were found to be in good agreement with the reported work functions of the contacting surfaces. The results for the charge with polymer materials differed from the work function values, presumably due to surface contamination. The surface energy of quartz particles calculated from the measured contact angle data showed that the tribo-charging increases the surface energy. Both polar and non-polar components computed using Fowkes and Owens-Wendt approaches showed that these components increase after tribo-electrification. However, the polar component divided into acid and base parts, as in van Oss approach, manifest decreasing acid part and increasing base part. Since quartz charged negatively during tribo-charging with metal surfaces and therefore suggests acceptance of electrons, the determined acid–base surface energy components are consistent with the charge transfer process. The results also elucidate an explicit correlation between the charge generated by powders and the surface acceptor (acid) and donor (base) electronic state and thereby the work functions. Thus a method for characterising the changes in surface energetic structure of solids during tribo-electrification in terms of acid–base parameters of electron transfer between the contacting surfaces has been described for the first time. [Copyright &y& Elsevier]

Abstract: The interaction of four benzyl derivatives with silica surface sites in anhydrous cyclohexane is investigated. The strength and extent of adsorption is determined from the Langmuir adsorption isotherm. The enthalpy of immersion is determined microcalorimetrically, which is recalculated to the enthalpy of adsorption. The aim is to distinguish between the Lewis-type (electron exchange) and Brønsted-type (proton exchange) of interaction by selecting methanol–acetone and acetic acid–methylamine, respectively as acid–base substituent in benzene. Moreover, the experiments were performed in anhydrous cyclohexane in order to screen out hydrocarbon interactions from the energy balance. The monomolecular adsorption is also distinguished from the bulk wetting of solids. The results are evaluated in terms of possible proton exchange in anhydrous media. [Copyright &y& Elsevier]

Surface defect-assisted non-radiative recombination is one of major detrimental factors limiting the development of efficient and stable perovskite solar cells (PSCs). The ionic characteristic of perovskite absorbers facilitates passivation of diverse defects through the interaction of specific ending functional groups of organic molecules. Here, the passivation mechanism of a bifunctional organic molecule, 4-methoxyphenylacetic acid (MPA), on the defects within perovskite absorbers is systematically investigated. Density functional theory and X-ray photoelectric spectroscopy confirm that the keto-oxygen atom of carboxylic acid in the MPA mainly passivates Pb–I antisite through Lewis base-acid interaction, while the O-donor of the methoxy group from MPA heals the undercoordinated Pb2+ on the perovskite absorbers surface via a coordination bond. The synergetic passivation of two functional groups significantly reduces the defect density and thus recombination loss, which is confirmed by the space charge limited current, time-resolved photoluminescence (PL) spectroscopy and PL mapping. The capacitance-voltage measurement proves that MPA treatment enhances the built-in potential to accelerate the separation of photogenerated charges within perovskite absorbers. As a result, MPA-treated PSCs achieve a champion efficiency of 22.32% (relatively to 20.97% of the control) coupled with improved environmental tolerance for PSCs on ITO/glass and 19.34% for PSCs on flexible ITO/polyethylene terephthalate. [Display omitted] • The bifunctional 4-methoxyphenylacetic acid (MPA) synergistically passivates defects. • The mechanism of passivation is systematically investigated. • MPA treatment enhances V bi and reduces non-radiative recombination losses. • The PCEs of optimized cells reach 22.32% on ITO/glass and 19.34% on ITO/PET. [ABSTRACT FROM AUTHOR]

Abstract: Surface Lewis acid–base properties are significant for polymers materials. The acid constant, K a and base constant, K b of many polymers were characterized by some researchers with inverse gas chromatography (IGC) in recent years. In this paper, the surface acid–base constants, K a and K b of 20 kinds of polymers measured by IGC in recent years are summarized and discussed, including seven polymers characterized in this work. After plotting K b versus K a, it is found that the polymers can be encircled by a triangle. They scatter in two regions of the triangle. Four polymers exist in region I. K b/K a of the polymers in region I are 1.4–2.1. The other polymers exist in region II. Most of the polymers are relative basic materials. [Copyright &y& Elsevier]

Abstract: The most common procedures to extract both the dispersive (Lifshitz–van der Waals) and specific (polar/acid–base) interactions from wetting experiments are critically evaluated. For example, the very useful (vOCG) model of van Oss–Chaudhury–Good has been found to frequently produce artificial and enforced basic surface energy values which require a systematic intrinsic consistency test. Therefore, dramatically simplified models are developed assuming mono–bi- and mono–mono-dentate interactions. From an exceptionally extensive cross-correlation, it is shown that the mono–mono-dentate model complies with a symmetric model for enthalpic interactions introduced by Drago. Moreover, first hand experimental information is used in order to evaluate key parameters such as Girifalco–Good quotient and work of wetting. It is shown that a match of the surface tension of the probe liquids and the surface energy of the solids is required to obtain meaningful results. The aim is to distinguish Brϕnsted proton exchange equilibrium from Lewis electron polarisation type of adduct formation. In order to evaluate this separation, the influence of pH and ionic strength on the state of silica is tested. The contribution of impurities as well as the presence of a vapour film are considered as sources of errors. [Copyright &y& Elsevier]

An important factor in achieving maximum adhesion of a particular coating system to the substrate lies in the proper preparation of the substrate prior to the application of paint. The Lewis acid-base properties of the outer metal surface play a determinant role in many of these applications, and the chemical reactions involved therein. In this work, the wetting properties of a low carbon aluminium killed (LCAK) substrate have been largely modified by a chemically activated surface treatment. XPS analysis was performed on the surface. Wettability in water, a polar and protic probe liquid, and in α-bromonaphthalene, a non-polar and aprotic probe liquid, of the LCAK surface is strongly modified when the LCAK surface is treated with dilute formic acid and warm water. Formic acid forms formate ions which have a higher reactivity with respect to molecular species and are able to react with the exposed surfaces, changing the relative structure of the hydroxyl layer. [ABSTRACT FROM AUTHOR]

Synthesis of chromotropic copper(II) mixed ligand complexes of o-hydroxy benzoyl derivatives (L1) and dinitrogen bases (L2), general formula Cun(L1)(L2)nXn; where n=1 or 2, L1=4,6-diacetyl-resorcinol (H2DACR), o-hydroxy benzaldhyde (HOHBZ) or o-hydroxy acetophenone (HOHAP), L2=N,N,N′,N′-tetramethylethylenediamine (Me4en), 1,10-phenanthroline (phen) or bipyridine (bipy) and X=ClO4−, NO3− or Br− have been reported. Spectral, magnetic and molar conductance measurements as well as analytical data of these complexes show either mononuclear structure for OHBZ and OHAP or binuclear structure for DACR complexes. The IR stretching vibration frequencies of Cu&z.sbnd;N and Cu&z.sbnd;O are linearly correlated with the d–d absorption frequencies. The d–d absorption bands of Me4en-complexes in weak donor solvents suggest square-planar, distorted octahedral and distorted trigonal bipyramid geometries for the perchlorate, nitrate and bromide complexes, respectively. However, an octahedral structure is identified for the complexes in strong donor solvents. Perchlorate complexes show a remarkable color change from violet to green as the donor ability of the axial ligand increases, whereas bromide complexes are mainly affected by the Lewis acidity of the axial ligand. Specific and non-specific interactions of solvent molecules with the complexes are investigated using the unified solvation model. Calculations of the electronic transition probability (f) of the d–d band along with molecular orbital calculations of ligands have been carried out and correlated with the experimental data. [Copyright &y& Elsevier]

We present our new findings about the causes of discrepancies between the measured and calculated liquid-liquid interfacial tensions derived from contact angles. The calculated ones are based on either the equation developed by Fowkes or that by van Oss, Chaudhury and Good (VCG), while the measured ones are based on the sessile drop, weight-volume by Jańzuk et al. and the axisymmetric drop shape analysis (ADSA) by Kwok and Neumann. Indeed, there are deviations between the calculated and measured results. For an immiscible liquid-liquid or liquid-solid interface, we prefer to employ Harkins spreading model, which requires the interfacial tension to be constant. However, for the initially immiscible liquid-liquid pairs, we propose an adsorption model, and our model requires the interfacial tension to be varying and the surface tensions of bulk liquids at a distance from the interface to remain unchanged. Thus, the difference between the initial and final interfacial spreading coefficients (S[sub i]) equals the equilibrium interfacial film pressure (π[sub i])[sub e]. According to our findings, the calculated interfacial tension represents the initial value (γ[sub 12])[sub o], which differs from the equilibrium value (γ[sub 12])[sub e] obtained experimentally after some time delay. This expected gap at a reasonable time frame is chiefly caused by the equilibrium interfacial film pressure between the two liquids. The initial (or calculated) interfacial tension can be positive or negative, while the equilibrium (or measured) one can reach zero. In fact, the former is shown to have more predictive value than the latter. A negative initial interfacial tension is described to favor miscibility or spontaneous emulsification but it tends to revert to zero instantaneously. Thus, a miscible liquid mixture should have zero interfacial tension. In response to recent papers by Kwok et al., we show that the disagreements between the calculated and measured interfacial tensions are definitely not caused by the failure of the VCG approach. Correct interfacial tensions are calculated for liquid pairs containing formamide or dimethyl sulfoxide (DMSO) by using the dispersion components cited in Fowkes et al.'s later publication. With the corrected surface tension components, the equilibrium interfacial film pressures (π[sub i])[sub e]'s for at least 34 initially immiscible liquid pairs have been calculated. These values are generally lower than the corresponding spreading pressures π[sub e]'s obtained by others using the Harkins model. Recently, we established a relationship between these two film pressures with the Laplace equation and found a new criterion for miscibility to be (π[sub i])[sub e] = π[sub e]. [ABSTRACT FROM AUTHOR]

• The CO 2 -alcohol complex due to the Lewis acid-base interaction is treated as their cross-association. • According the different association schemes, the PVT of CO 2 shows increasing accuracy. • The consideration of self-association of CO 2 improves the VLE behavior within the high-pressure region. Due to the electropositivity of the carbon atom in CO 2 which results from its lower electron density compared to that of the oxygen atom, CO 2 molecules can act either as proton acceptor or electron acceptor. The specific intermolecular interaction (i.e., Lewis acid-base interaction) between CO 2 and organic chemicals with electron donor groups exists, and this phenomenon is supported by many experimental studies using spectrometry and ab initio studies. CO 2 /alcohol solvent systems under high-pressure conditions are important for supercritical extraction, dehydration of alcohols, and extraction of natural products. Furthermore, the study of the complex between CO 2 and alcohols due to the Lewis acid-base interaction is crucial for understanding the solvation process under high-pressure conditions, and for the development of thermodynamic models. In this study, the Lewis acid-base interaction between alcohols and CO 2 is treated as a hydrogen bonding interaction, and according to the different association schemes for CO 2 , the effect on the phase behavior of the CO 2 /alcohol systems at high pressure was investigated using the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) model. Taking into consideration the self-association of CO 2 yields a more satisfactory performance in the high-pressure region than it would without, and increasing association sites of CO 2 do not lead to a better performance. In addition, the cross-association energy (i.e., Lewis acid-base interaction energy) parameter is estimated by directly regressing the experimental data over the entire temperature and pressure range, and the calculated results show an improved performance even at much higher pressures. It was found that strong cross-association interactions lead to higher cross-association in both liquid and vapor phases, which contributes to the improved phase behavior at high-pressures. [ABSTRACT FROM AUTHOR]

• Proline is added in PSCs, exhibiting PCE=19.6%. • Orientational crystallization was realized by steric hindrance effect. In perovskite solar cells, the molecule configuration of Lewis adducts closely related with its coordination ability, which needs careful design. In this work, two amino acids, circular proline and linear glycine are applied to reveal the steric effect of the Lewis-acid base additives. The proline with configuration and analogous size with Pb-Pb distance in perovskite crystals realizes better coordination effect, greatly promotes the perovskite crystal growth and trap states passivation. The PSCs with proline as additives in perovskite (PVK) exhibit the highest efficiency of 19.6% under 1 sun AM1.5, compared with 18.5% of PSC with glycine additive and 17.8% of the pristine PSCs. This work highlights steric effect should be considered when choosing and designing the Lewis adducts. [ABSTRACT FROM AUTHOR]

The carrier non-radiative recombination and instability of device caused by the inherent defects are main factors limiting development of perovskite solar cells (PSCs). During the fabrication process of a PSC device, perovskite films often produce Pb 0 and I 0 defects. This paper reports a strategy for synergistic optimization of perovskite films by defects passivation and surface modification. The doping of phthalide (PT) in the Pb-rich (CH(NH 2 ) 2 ) 1-x (CH 3 NH 3 ) x PbI 3 film can passivate lead cation defects, and the modification of 1-iodooctadecane (1-IO) can reduce halogen anion defects and improve stability of PSCs owing to its hydrophobicity. The PT and 1-IO optimized device achieves a power conversion efficiency (PCE) of 22.27%. The optimized PSCs remain 93.2% of the initial PCE when placed in air environment (relative humidity of 10%, 25 °C) more than 70 days. The PT and 1-IO synergistic optimization provides a novel strategy for improving the performance and stability of PSCs., (© 2021 Wiley-VCH GmbH.)

Abstract: Using the anion receptor tris(penftafluorophenyl) borane as an additive to non-aqueous electrolytes, the solubility of solid Li2O2 can be dramatically increased through the Lewis acid–base interaction between boron and peroxide. The complexed boron-peroxide ions can be electrochemically oxidized with much better kinetics than the oxidation of solid Li2O2 on a carbon powder microelectrode. This discovery could lead to a new avenue for the development of high capacity, high rate, rechargeable, Li–Air batteries. [Copyright &y& Elsevier]

Creatinine (Cre) level is closely related to renal function of human. Therefore, it is of great significance to develop highly sensitive and selective tools for Cre determination. Herein, a turn-on fluorescence metal organic framework (MOF) sensor, which was synthesized by post-synthetic modification of 8-hydroxy-2-quinolinecarboxaldehyde (HQCA) and Al3+ toward UiO-66-NH 2 , was applied to detect Cre. The turn-on of fluorescence was attributed to the formation of Lewis acid-base complexes between Cre and Al3+, which led to the interruption of energy transfer and electron transfer from UiO-HQCA to Al3+. Thus, the fluorescence quenching of UiO-HQCA-Al caused by Al3+ was recovered. Results showed that the sensor exhibited wide linear range (0.05–200 μM), high sensitivity (detection limit = 4.7 nM), fast response time (1 min), and high selectivity toward Cre. The practicability of the sensor was verified by detecting Cre in human serum and urine samples. The present work was the first attempt that MOF material was used as a fluorescence sensor to detect Cre, which exhibited great application prospects in clinical diagnosis of related diseases. Image 1 • MOFs were used for the fluorescence detection of creatinine for the first time. • A turn-on fluorescence sensor was designed by post-synthetic modification. • Quinoline was firstly employed for post-synthetic modification of UiO-66. • The sensor exhibited high sensitivity, rapidity, and specificity toward creatinine. [ABSTRACT FROM AUTHOR]

• Zinc sulfide can catalyze the transformation of polysulfide. • The anion vacancy produced by the phase transition of zinc sulfide is helpful to capture polysulfide. • Carbon nanosheet skeleton is beneficial to the reuse of active substances. • ZnS/NCNS can accommodate a cathode with high areal loading. Stabilizing the lithium anode while inhibiting the shuttle effect to achieve stable circulation under high sulfur loading is an inevitable problem for the commercialization of lithium-sulfur batteries. A low cost of raw materials and a simple synthesis are also important prerequisites for product commercialization. In this paper, zinc sulfide (ZnS) nanoparticles embedded in nitrogen-doped 3D-carbon nanosheets (NCNS) are proposed as modified separator materials. During high-temperature carbonization of the carbon materials, a zinc sulphide phase transition occurs, resulting in an anion vacancy (S2-) and an unsaturated Zn centre. While maintaining catalytic activity, the unsaturated Zn centre in ZnS acts as a Lewis acid to form a coordinate bond with the polysulfide. Furthermore, a uniform distribution of N heteroatoms can effectively regulate Li+ flux through the separator, thereby achieving a stable cycle for the lithium anode. A cell with the ZnS/NCNS-modified separator can achieve a stable cycle at 0.5 C and superior electrochemical performance even with an areal sulfur loading of 6 mg cm−2. An excellent reduction in self-discharge was also confirmed by a 4% capacity attenuation after resting for 4 days. This work provides new insight on the design and preparation of novel separators for highly stable Li–S batteries via a "green" and cost-effective approach. [ABSTRACT FROM AUTHOR]