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It has been shown that the wettability of a material synthesized in the interfacial layer of a liquid/liquid heterogeneous system can be controlled by local vibrations. The influence of the nature of an organic acid, a metal, and a solvent on the contact angle of a material adhered to various substrates has been studied. It has been found that, under local vibrations, a material is synthesized with a more ordered structure, a higher roughness, a lower water content, and, as a consequence, a larger contact angle. Hydrophobic coatings with contact angles of 100–163° have been obtained on the studied substrates, with the coatings retaining their water-repellent properties under atmospheric conditions for a long time. [ABSTRACT FROM AUTHOR]

In the presented work, a new original procedure for the interfacial synthesis of the magnetic nanoparticles (MNPs) modified with a polymer shell and functionalized by an ionic liquid or a deep eutectic solvent in aqueous biphasic systems (ABSs) is proposed. The synthesis is carried out at the interface of immiscible liquids based on aqueous solutions of polyethylene glycol and inorganic salts. The advantages of the ABSs are biocompatibility, availability, and the high solvating properties of the components, which leads to control the composition and size of the prepared MNPs. The synthesis of the Fe3O4@PEG, Fe3O4@PEG@Cyphos IL 101, and Fe3O4@PEG@TOPO/butanol MNPs has been provided for biomedical and analytical applications. The morphology and structure of MNPs have been characterized by scanning and transmission electron microscopy, thermogravimetry, X-ray diffraction, and FT-IR spectroscopy. The average diameter of the MNPs is 12–14 nm with a narrow size distribution. Their superparamagnetic nature has been described using magnetometry. The synthesis parameters have been optimized and statistically analyzed using response surface methodology. The developed approach of interfacial synthesis can be potentially scaled up and/or be used to obtain nanoparticles of various composition and application. [ABSTRACT FROM AUTHOR]

Two‐dimensional polymers (2DPs) and their layer‐stacked 2D covalent organic frameworks have recently emerged as nonlinear optical (NLO) materials for potential applications in optics. However, the chemistry for designing third‐order NLO 2DP films with large nonlinear absorption coefficient (β) has remained a mystery. Herein, three highly crystalline porphyrin‐integrated 2D polyimines (named as 2DPI‐Zn‐Azo, 2DPI‐2H‐Azo, and 2DPI‐Zn), which are homogeneous films showing large lateral areas over cm2, uniform transparency, and thickness of tens of nanometers are reported. Particularly, the 2DPI‐Zn‐Azo film comprising zinc porphyrin and –NN– displays a large saturable absorption under 532 nm and the highest β (−1.88 × 105 cm GW−1) among the three 2D polyimines, that is also 2–5 orders of magnitude higher than the state‐of‐art performance of photoactive small molecules, porphyrin‐integrated 2DPs, and inorganic 2D materials. Control experiments in combination with theoretical calculation discover that the embedding of metal centers and –NN– results in highly delocalized π‐electrons and narrow bandgap in 2DPI‐Zn‐Azo, which enables fast transfer of the photogenerated electrons after the light‐excited charge separation, thus boosting the NLO performance. This work opens up a new path for the construction of highly efficient third‐order NLO film materials, and pushes the development of 2DPs for optics and optoelectronics. [ABSTRACT FROM AUTHOR]

Monomers with low symmetries can form different topological structures in the preparation of organic two-dimensional (2D) materials. However, it remains challenging to modulate the topologies in practical synthesis. Leveraging theoretical insights into the formation energy of potential structural configurations, we report the topology modulation of a graphdiyne (GDY) derivative constructed from two-fold symmetric tetrakis(4-ethynylphenyl)ethene precursor by changing solvent combinations in a liquid-liquid interfacial system. An aqueous-organic (water-dichloromethane) interface afforded GDY with a kagome topology while a rhombic topology was formed at an organic-organic (hexane-acetonitrile) interface. A comprehensive evaluation of their structures and optoelectronic properties was conducted through various characterization techniques and theoretical computations. Our study provided new insights to modulate the topology of not only GDY but also other framework structures and obtain topologically pure materials in situations where different topologies are possible during practical synthesis. [ABSTRACT FROM AUTHOR]

Exploring innovative strategies for molecular structuring of dynamic materials that combine self‐correcting intrinsic reversibility with the robustness of covalent bonds, has been a long‐standing objective from applications perspective in fields ranging from molecular engineering to nanotechnology and interfacial science. To establish dynamic covalent chemistry approaches combined with interfacial polymerization, herein, a distinct synthetic approach is reported to develop disulfide‐bridged 2D polymeric C3N3S3 triazine thin‐films by interfacial thiol‐disulfide dynamic exchange process crosslinking tritopic planar 1,3,5‐triazine‐2,4,6‐trithiol molecular tectons via intermolecular disulfide formation in the presence of I2 vapors at the air/water interface under redox condition. The resulting centimeter‐scale polymeric thin‐films are covalently cross‐linked, dynamic in nature, featuring tunable thickness (6–200 nm) and significant morphological variations are realized under the influence of varying reaction time, concentration and types of reducing agents. Notably, C3N3S3 polymer thin films exhibit a transflectance of around 99.5% in the range from 430 to 1800 nm, show high refractive indices (1.730–1.488) and optical anisotropy with uniaxial negative birefringence. The C3N3S3 free‐standing polymer thin‐films can be easily transferred to different substrates or possibly into application‐relevant forms for device fabrications, making this useful from materials application perspective. [ABSTRACT FROM AUTHOR]

Silicon anodes with high energy density are prone to mechanical deformation during cycling, including fracture, pulverization, and delamination from conductive materials, due to their large volume expansion and contraction. Although significant attention is paid to outer interface engineering such as surface coating and electrolyte design in order to maintain a steady solid electrolyte interphase (SEI), there are currently few strategies in place for stabilizing the inner interface between Si and conductive carbon host materials. In this work, it is reported that an interfacial SiC chemical bonding enhances the interaction between Si and carbon, which in turn suppresses nano‐sized void evolution and ensues Si delamination. Through the open‐edge structure of carbon nanotube (OCNT), it is demonstrated that graphitic edge planes enable to evoke of interfacial SiC specifically at the junction without overgrowth toward the bulk. As a result, an Si‐graphite composite consisting of interfacial SiC exhibits a sF cycling life (79.5% for 300 cycles at 3C charging), as well as lower overpotential under high current density up to 5C compared to paired LiNi0.6Co0.2Mn0.2O2 (NCM) cathode in pouch full‐cell tests. This study highlights the significance of inner interface engineering for developing high‐energy density Si‐based anodes toward fast charging and long‐term stability. [ABSTRACT FROM AUTHOR]

Electrochemical sensing is considered as one of the most promising approaches for quick, reliable, and on-site detection and monitoring of arsenic (As) levels in water. However, the unavailability of stable, selective, and affordable electrode materials hampers the development of portable, cost-effective, reliable, and practically applicable arsenic-sensing electrochemical devices. In this article, we describe a straightforward biphasic synthesis method for the crafting of sulfur-doped reduced graphene oxide (S-rGO)-supported Prussian blue (PB) nanodeposits (S-rGO/PB), a nanocomposite with exceptional stability and activity for selective and sensitive electrochemical sensing of As. The S-rGO/PB is demonstrated to selectively and sensitively electrocatalyze the As(0)/As-(III) and As-(III)/As-(V) charge transfer processes via the participation of the Fe-(II)/Fe-(III) cycle as revealed by X-ray photoelectron spectroscopy, thereby ensuring accurate and sensitive electrochemical sensing of As in water samples. We demonstrate that with the S-rGO/PB electrode, As-(III) can be sensed via differential pulse voltammetry (DPV) with sensitivity values of 1.79 (As(0)–As-(III)) and 10.69 μA ppb–1 cm–2 (As-(III)–As-(V)) and limits of detection as low as 0.0104 and 0.0536 ppb, respectively. Alongside real-time applicability, the S-rGO/PB is demonstrated to exhibit excellent stability and specificity toward arsenic sensing even in the presence of other interferents. Importantly, the As-(III) estimates obtained for real water samples using DPV over S-rGO/PB closely match the estimates obtained with atomic absorption spectrometry, a highly expensive and sophisticated state-of-the-art technique known for its accuracy in estimation of the sub-ppb traces of heavy metals. The presented results suggest that the S-rGO/PB composite is a promising electrode material that can facilitate the design and development of portable, affordable, reliable, and practically applicable electrochemical setups for on-site sensing and electrodetoxification of As-(III) in water samples. The availability and accessibility of such setups are a must for the worldwide success of arsenic mitigation initiatives, particularly in underdeveloped and impoverished nations. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY) is an exclusive carbon allotrope with a two‐dimensional (2D) structure that can be synthesized in laboratory settings. Due to its distinctive 2D structure and excellent electronic properties, GDY has captured the great interest of researchers. In addition, the porous nature and high specific surface area of GDY afford numerous storage sites and channels, rendering it highly promising for diverse applications. The synthesis of GDY still faces a multitude of obstacles and challenges. Developing new synthesis methods towards high‐quality GDY is particularly significant. As such, we here presented an overview of the reported synthesis techniques for GDY, categorizing them into three distinct approaches: interfacial synthesis, solid‐phase synthesis, and solution‐phase synthesis. This comprehensive summary provides valuable references for addressing the persistent challenges in the synthesis of GDY. In the end, an outlook sheds light on future research of the GDY materials. [ABSTRACT FROM AUTHOR]

Two-dimensional polyimide covalent organic framework (2D PI-NT COF) films were constructed on indium tin oxide-coated glass substrates to fabricate two-terminal sandwiched resistive memory devices. The 2D PI-NT COF films condensated from the reaction between 4,4',4″-triaminotriphenylamine and naphthalene-1,4,5,8-tetracarboxylic dianhydride under solvothermal conditions demonstrated high crystallinity, good orientation preference, tunable thickness, and low surface roughness. The well-aligned electron-donor (triphenylamine unit) and -acceptor (naphthalene diimide unit) arrays rendered the 2D PI-NT COF films a promising candidate for electronic applications. The memory devices based on 2D PI-NT COF films exhibited a typical write-once-read-many-time resistive switching behavior under an operating voltage of +2.30 V on the positive scan and -2.64 V on the negative scan. A high ON/OFF current ratio (>106 for the positive scan and 104-106 for the negative scan) and long-term retention time indicated the high fidelity, low error, and high stability of the resistive memory devices. The memory behavior was attributed to an electric field-induced intramolecular charge transfer in an ordered donor-acceptor system, which provided the effective charge-transfer channels for injected charge carriers. This work represents the first example that explores the resistive memory properties of 2D PI-COF films, shedding light on the potential application of 2D COFs as information storage media.

Metal-organic framework (MOF) membranes are potentially useful in gas separation applications. Conventional methods of MOF membrane preparation require multiple steps and high-pressure conditions. In this study, a reliable one-step interfacial synthesis method under atmospheric pressure has been developed to prepare zeolitic imidazolate framework-8 (ZIF-8) membranes supported on porous α-Al2O3 disks. To obtain optimal ZIF-8 membranes, three reaction parameters were investigated, namely, reaction temperature, reaction time, and concentration of the organic linker (i.e., 2-methylimidazole). The growth of ZIF-8 membranes under various parameters was evaluated by field-emission scanning electron microscopy, and the optimal synthesis conditions were determined (i.e., 80 °C for 12 h in 50 mM of 2-methylimidazole). The as-synthesized ZIF-8 membranes were then applied to CO2/N2 gas separation, which exhibited a maximum separation factor of 5.49 and CO2 gas permeance of 0.47 × 10−7 mol·m−2·s−1·Pa−1.

A carbon–carbon-linked, ultrathin, two-dimensional (2D) polymer film was prepared at the air/water interface through photochemically triggered [2 + 2] cycloaddition. The preorganization of the monomers on the water surface and the subsequent photo-polymerization led to the successful preparation of the ultrathin 2D polymer film. The obtained film is continuous, free standing, and has a large area (over 50 μm2). Transmission electron microscopy (TEM) and atomic force microscopy (AFM) give clear evidence of the ultrathin film morphology. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) indicate successful photo-induced [2 + 2] polymerization. [ABSTRACT FROM AUTHOR]

The study shows that the materials of interfacial formations formed at the interface of two immiscible liquids, an aqueous solution of a lanthanide salt and a solution of di(2-ethylhexyl)phosphoric acid in a solvent, can have different hydrophobicity depending on the synthesis time. The surface roughness and the contact angle of the substance transferred to different substrates (glass, duralumin, copper) were measured. It was established that external vibration in the interfacial layer of the system during synthesis and self-assembly affects the hydrophobicity of the substance. A dependence between the contact angle and the surface roughness was established. [ABSTRACT FROM AUTHOR]

A system of an aqueous solution of a lanthanide salt di-(2-ethylhexyl)phosphoric acid in a diluent (heptane, toluene, carbon tetrachloride) is used to show that the local vibration on the interfacial layer in a system of two immiscible liquids during interfacial synthesis can produce a qualitative change in the wettability of the substrate onto which the material of interfacial formations is transferred. This makes the surface hydrophobic or hydrophilic due to different structuring, as in the lotus leaf effect. By varying the composition of the system, the conditions of the process, and the parameters of the external force field, a material with a given angle of contact (30° to 163°) can be obtained, improving the consumer qualities of its carrier. [ABSTRACT FROM AUTHOR]

The synthesis of crystalline covalent organic frameworks (COFs) has in principle relied on reversible dynamic chemistry. A general method to synthesize irreversibly bonded COFs is urgently demanded for driving the COF chemistry to a new era. Here we report a universal two-step method for the straightforward synthesis of irreversibly amide-linked COF (AmCOF) membranes by autocatalytic interfacial polymerization (AIP). Highly crystalline amide and imine bilinker COF (AICOF) membranes are readily synthesized by AIP strategy which ingeniously leverages interfacial polymerization to generate amide units followed by an autocatalytic condensation that forms imine bonds. Then, the fully amide-linked AmCOF membranes with Turing structures can be prepared through irreversible linker renovation. The universality of this method has been exemplified by nine AmCOF membranes. Among them, the AmCOF-1 membrane exhibits superior performance for H 2 O 2 photosynthesis (4353 μmol g -1  h -1 ) and high stability, enabling continuous production of H 2 O 2 under sunlight for 150 h without sacrificial agents. Mechanistic investigations reveal that the greatly improved properties are attributable to the built-in robust amide knots, facilitating full separation of electrons and holes, ultra-long exciton diffusion length, and fast dissociation of excitons within the AmCOF channels., (© 2025 Wiley-VCH GmbH.)

Metal-organic frameworks (MOFs) are normally moisture-sensitive and unstable in aqueous environments, which has considerably limited their practical applications because water/moisture is ubiquitous in many industrial processes. New materials with superior water stability are, therefore, in great demand and vital to their practical applications. Here, a novel oil/water interfacial assembly strategy is demonstrated for the synthesis of a new class of metal-organic monoacid framework (MOmAF) with exceptional water stability and chemical stability. Superhydrophobic 2D sheets are synthesized at room temperature, while 1D nanotubes are obtained via the self-scrolling of their 2D sheets for the first time. In addition, a simple sequential drop-casting method is developed to coat as-synthesized MOmAF structures onto porous membranes. This can potentially open up new avenues in the design of superhydrophobic self-cleaning MOmAF materials without tedious post-synthetic modifications and usher in a new class of materials meeting industrial needs., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

1D APbX3 (A = Cs, MA, FA, X = Cl, Br, I) nanorods (NRs) show potential for the future integrated optoelectronic devices as the ideal building blocks due to their outstanding optoelectronic performances. However, there is still a lack of high‐efficiency controllable strategies to synthesize CsPbX3 NRs. An interfacial synthesis strategy is shown here to fabricate CsPbBr3 NRs by inserting Pb2+ into postsynthetic CsBr nanocrystals in vortex method at the water‐hexane interface. The water phase can intrinsically separate from the hexane phase in such a system and take away excess Pb2+ and other side reaction salts. Additionally, without additional ligand assisted growth, the whole reaction system could result in a very clean surface of CsPbBr3 NRs, eliminating the further purification process. The new approach for interfacial synthesis paves the way for efficient synthesis of CsPbBr3 nanorods. [ABSTRACT FROM AUTHOR]

In this study, a ZIF-8 thin layer deposited on the surface of a hydrolyzed polyacrylonitrile (HPAN) membrane was used for highly efficient humic acid removal. The thin ZIF-8 layer was synthesized by using a two-step interfacial synthesis method, based on liquid–liquid interfacial coordination polymerization. The formation of a continuous ZIF-8 layers was confirmed by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The effects of the synthesis conditions including reaction time, precursor concentration, and other operating conditions on the ZIF-8 composite membrane performance were studied using humic acid solution as organic waste. The results showed when the reaction time was extended, or when the precursor concentration was increased, the ZIF-8 layer deposited on the membrane surface became denser. Compared with the unmodified HPAN substrate, the composite membrane deposited with the ZIF-8 layer showed better processing ability for organic matters due to the strong electrostatic interaction of organic matter with the ZIF-8@HPAN membrane and the ZIF-8 particles unique structural characteristics, which shows a great application prospect for humic acid treatment compared with other membrane technologies. [ABSTRACT FROM AUTHOR]

We report a facile strategy to prepare a large amount of ultrathin graphdiyne (GDY) with good crystallinity in the mixture of oil–water systems. By simply mixing the solution of GDY monomer in CHCl3 and the copper acetate solution as a catalyst in water and stirring at room temperature, ultrathin GDY films with a thickness of ∼4 nm were obtained in a yield of 95 %. This work provides a feasible path for the substantial preparation of GDY films and may pave the way to the development of substantial preparation of the GDY materials. [ABSTRACT FROM AUTHOR]

Microcapsules have been widely used in drug carriers, nano/microreactors, artificial organelles for their empty space and functional shell. Microcapsules synthesized from spherical liquid-liquid interface show ultrathin shell and large cavities. However, spherical liquid-liquid interfaces generated by stirring or sonicating are difficult in controlling the droplet size and preventing their coalescence, which results in inhomogeneous capsules. Here, we demonstrate a microfluidic interfacial synthetic method to produce microcapsules using the hot covalent organic polymers (COPs) coupled with Schiff-base reaction. A very high throughput of uniform and individual microdroplets about ~1400 min−1 was generated under high flow rate for COP capsules fabrication. Acidic catalyst promoted amine and aldehyde condensation that reacted less than 1 ​s assured the polymerization occurred at the liquid-liquid interface regardless of the diffusion intensification in microfluidic system. COP capsules with shell thickness around 50 ​nm were flexible enough to response to slight interior capillary force and exterior filtration force to form origami structure and sealed flat membrane, respectively. Each of the interfacial synthesized capsule expressed large capacity by encapsulating 1.41 ​× ​10−2 ​μg SiO2 nanoparticles as theoretically calculated. Thus, these properties make the COP capsules promising in, but not limited to, fast drug delivery and microreactors.

Abstract A fluorescent monolayered two‐dimensional polymer (2DP) containing both tetraphenylethylene (TPE) and imine linkages is synthesized at air‐water interface using the Langmuir‐Blodgett method. We designed TPE‐based monomers with long distances between the TPE and the imine linkages to avoid the charge transfer and therefore keep the fluorescence. A monolayered 2DP provided with more than 104 μm2 in domain size and around 0.8 nm thickness was obtained through a successive Schiff base reaction at air‐water interface. The nanostructures and fluorescent property of 2DP films were characterized by optical microscopy, SEM, TEM, AFM and fluorescence spectrum. Most importantly, the tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP.

Membrane-based separation has been demonstrated as an ecofriendly technology in the field of energy and the environment. However, simultaneously enhancing the permeability and selectivity of membranes remains a great challenge due to the lack of a tunable and ordered pore structure. Herein, a facile approach for the interfacial synthesis of polyamide (PA)-supported covalent organic framework (COF) nanomembranes was introduced for the first time, in which interfacial crystallization of COF was formed in a two-phase interface using 1,3,5-triformylphloroglucinol (Tp) and 2,5-diethoxy-terephthalohydrazide (Dth) as building units. The thickness of COF layers covered on a PA substrate ranged from 90 to 550 nm. The as-prepared COF nanomembranes (defined as Tp-Dth/PA) possessed many superior properties, including high porosity, tunable and ordered micropores, and good chemical/mechanical stability. Arising from the synergetic effect of the hydrophilic PA support and highly ordered porous structure of COF layers, the obtained Tp-Dth/PA nanomembranes exhibited outstanding performances in terms of permeability and rejection efficiency, in which the water permeance was up to 31.7 L m–2 h–1 bar–1 and the retention rates for congo red (CR) and alcian blue 8GX (AB) were higher than 99.5 and 99.8%, respectively. Moreover, molecular separation of AB from a mixed aqueous solution was achieved with the Tp-Dth/PA nanomembranes based upon the principle of the size-exclusion effect. In addition, the Tp-Dth/PA nanomembranes could be successfully applied to the selective separation of dyes from industrial wastewater, demonstrating their great potential in water treatment. [ABSTRACT FROM AUTHOR]

We explore the charge transport properties of phytic acid (PA) doped polyaniline thin films prepared by the surfactant monolayer‐assisted interfacial synthesis (SMAIS). Structural and elemental analysis confirms the inclusion of PA in the thin films and reveals a progressive loss of crystallinity with the increase of PA doping content. Charge transport properties are interrogated by time‐resolved terahertz (THz) spectroscopy. Notably, independently of doping content and hence crystallinity, the frequency‐resolved complex conductivity spectra in the THz region can be properly described by the Drude model, demonstrating band‐like charge transport in the samples and state‐of‐the‐art charge carrier mobilities of ≈1 cm2V−1s−1. A temperature‐dependent analysis for the conductivity further supports band‐like charge transport and suggest that charge carrier mobility is primarily limited by impurity scattering. This work highlights the potential of PA doped polyaniline for organic electronics. [ABSTRACT FROM AUTHOR]

Advances in multi-electron transfer materials and architectured electrodes are two important strategies for innovations in electrochemicalenergy storage. The attainment of both by interfacial electrodeposition of freestanding PPy-PEDOT copolymer films was reported. The composition of the copolymer was verified by FTIR and XPS spectra.The dispersion and microstructure of PPy and PEDOT were studied by EDX mapping and SEM. The capacitive performances of the copolymer films were studied by electrochemical measurements. The results show the copolymer film is composed of PPy and PEDOT with homogeneous distribution in a certain proportion.The SEM images show the film exhibits heterogeneous microstructure and has an open porous 3D network microstructure. Electrochemical characterization shows that the copolymer film is an excellent supercapacitor electrode material with high specific capacitance, good power capability and cycle performance. The multi-electron transfer nature of the copolymer, the copolymerization synergistic effects and the unique microstructure are responsible for the improved charge-discharge performances.

Two‐dimensional polymers (2DPs) are a class of atomically/molecularly thin crystalline organic 2D materials. They are intriguing candidates for the development of unprecedented organic–inorganic 2D van der Waals heterostructures (vdWHs) with exotic physicochemical properties. In this work, we demonstrate the on‐water surface synthesis of large‐area (cm2), monolayer 2D polyimide (2DPI) with 3.1‐nm lattice. Such 2DPI comprises metal‐free porphyrin and perylene units linked by imide bonds. We further achieve a scalable synthesis of 2DPI‐graphene (2DPI‐G) vdWHs via a face‐to‐face co‐assembly of graphene and 2DPI on the water surface. Remarkably, femtosecond transient absorption spectroscopy reveals an ultra‐fast interlayer charge transfer (ca. 60 fs) in the resultant 2DPI‐G vdWH upon protonation by acid, which is equivalent to that of the fastest reports among inorganic 2D vdWHs. Such large interlayer electronic coupling is ascribed to the interlayer cation–π interaction between 2DP and graphene. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) metal–organic framework nanosheets (MOF NSs) play a vital role in catalysis, but the most preparation is ultrasonication or solvothermal. Herein, a liquid–liquid interfacial synthesis method has been developed for the efficient fabrication of a series of 2D Ni MOF NSs. The active sites could be modulated by readily tuning the ratios of metal precursors and organic linkers (RM/L). The Ni MOF NSs display highly RM/L dependent activities towards 2e oxygen reduction reaction (ORR) to hydrogen peroxide (H2O2), where the Ni MOF NSs with the RM/L of 6 exhibit the optimal near‐zero overpotential, ca. 98 % H2O2 selectivity and production rate of ca. 80 mmol gcat−1 h−1 in 0.1 M KOH. As evidenced by X‐ray absorption fine structure spectroscopy, the coordination environment of active sites changed from saturation to unsaturation, and the partially unsaturated metal atoms are crucial to create optimal sites for enhancing the electrocatalysis. [ABSTRACT FROM AUTHOR]

The results of studies in the field of interfacial synthesis and interfacial formations in liquid–liquid systems are summarized. The mechanisms of the processes of interfacial synthesis are considered. Data on the self-assembly of nanoparticles, films, and 3D materials are given. The properties of materials of interfacial formations in systems with rare-earth elements and di(2-ethylhexyl)phosphoric acid, obtained both in the presence and absence of local vibrations, are described. It was established that materials obtained in the presence of local vibrations in the interfacial layer have higher density, melting point, and magnetic susceptibility and lower electric conductivity. The effect of force field parameters on the properties of interfacial formations is considered. Practical applications and prospects for research in the field of interfacial formations are discussed. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) conversion into value-added chemicals/fuels by utilizing solar energy is a sustainable way to mitigate our dependence on fossil fuels and stimulate a carbon-neutral economy. However, the efficient and affordable conversion of CO 2 is still an ongoing challenge. Here, we report an interfacially synthesized visible-light-active Ni(II)-integrated covalent organic frameworks (TaTpBpy-Ni COFs) film as a photocatalyst for efficient CO 2 conversion into carboxylic acid under ambient conditions. Notably, the TaTpBpy-Ni COFs film showed excellent photocatalytic activity for the carboxylation of various arylamines with CO 2 to the corresponding arylcarboxylic acid via C-N bond activation under solar-light irradiation. Moreover, this carboxylation protocol exhibits mild reaction conditions and good functional group tolerance without the necessity of using stoichiometric metallic reductants. This work shows a benchmark example of not only the interfacially synthesized COFs film used as a photocatalyst for solar-light energy utilization but also the selective solar chemical production system of arylcarboxylic acid directly from CO 2 .

Organic two-dimensional (2D) materials have become one of the emerging topics, due to their potential unique physical and chemical properties. The preparation of 2D polymers with large area, controllable thickness and long-range ordering features remains challenge. Many new organic 2D materials have been reported in the past few years. However, many organic 2D materials possess obvious disadvantages, including poor crystallinity, limited ordering size. Recently, Xinliang Feng's group at Dresden University of Technology reported the controllable preparation to crystalline two-dimensional polymer by surfactant-monolayer-assisted interfacial synthesis (SMAIS). The key of this method is the surfactant monolayers at the gas-liquid interface can limit molecules or precursors to the 2D interface, for further polymerization. The regulation of the repeating structure and crystallinity of as-prepared 2D polyaniline (2DPANI), 2D polyimide (2DPI) and 2D polyamide (2DPA) were very well studied. This method provides a new strategy for preparation of crystalline organic 2D polymers. [ABSTRACT FROM AUTHOR]

Despite the recent progress in the synthesis of crystalline boronate ester covalent organic frameworks (BECOFs) in powder and thin‐film through solvothermal method and on‐solid‐surface synthesis, respectively, their applications in electronics, remain less explored due to the challenges in thin‐film processability and device integration associated with the control of film thickness, layer orientation, stability and crystallinity. Moreover, although the crystalline domain sizes of the powder samples can reach micrometer scale (up to ≈1.5 μm), the reported thin‐film samples have so far rather small crystalline domains up to 100 nm. Here we demonstrate a general and efficient synthesis of crystalline two‐dimensional (2D) BECOF films composed of porphyrin macrocycles and phenyl or naphthyl linkers (named as 2D BECOF‐PP or 2D BECOF‐PN) by employing a surfactant‐monolayer‐assisted interfacial synthesis (SMAIS) on the water surface. The achieved 2D BECOF‐PP is featured as free‐standing thin film with large single‐crystalline domains up to ≈60 μm2 and tunable thickness from 6 to 16 nm. A hybrid memory device composed of 2D BECOF‐PP film on silicon nanowire‐based field‐effect transistor is demonstrated as a bio‐inspired system to mimic neuronal synapses, displaying a learning–erasing–forgetting memory process. [ABSTRACT FROM AUTHOR]

Single‐layer and multi‐layer 2D polyimine films have been achieved through interfacial synthesis methods. However, it remains a great challenge to achieve the maximum degree of crystallinity in the 2D polyimines, which largely limits the long‐range transport properties. Here we employ a surfactant‐monolayer‐assisted interfacial synthesis (SMAIS) method for the successful preparation of porphyrin and triazine containing polyimine‐based 2D polymer (PI‐2DP) films with square and hexagonal lattices, respectively. The synthetic PI‐2DP films are featured with polycrystalline multilayers with tunable thickness from 6 to 200 nm and large crystalline domains (100–150 nm in size). Intrigued by high crystallinity and the presence of electroactive porphyrin moieties, the optoelectronic properties of PI‐2DP are investigated by time‐resolved terahertz spectroscopy. Typically, the porphyrin‐based PI‐2DP 1 film exhibits a p‐type semiconductor behavior with a band gap of 1.38 eV and hole mobility as high as 0.01 cm2 V−1 s−1, superior to the previously reported polyimine based materials. [ABSTRACT FROM AUTHOR]

A fluorescent monolayered two‐dimensional polymer (2DP) containing both tetraphenylethylene (TPE) and imine linkages is synthesized at air‐water interface using the Langmuir‐Blodgett method. We designed TPE‐based monomers with long distances between the TPE and the imine linkages to avoid the charge transfer and therefore keep the fluorescence. A monolayered 2DP provided with more than 104 μm2 in domain size and around 0.8 nm thickness was obtained through a successive Schiff base reaction at air‐water interface. The nanostructures and fluorescent property of 2DP films were characterized by optical microscopy, SEM, TEM, AFM and fluorescence spectrum. Most importantly, the tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP. [ABSTRACT FROM AUTHOR]

Fundamental insights into the reaction kinetics of organic–inorganic lead halide perovskite nanocrystals (LHP NCs) are still limited due to their ultrafast formation rate. Herein, we develop a water–oil interfacial synthesis of MAPbBr3 NCs (MA=CH3NH3+), which prolongs the reaction time to tens of minutes. This method makes it possible to monitor in situ the formation process of MAPbBr3 NCs and observe successive spectral evolutions from 438 to 534 nm in a single reaction by extending reaction time. The implementation of this method depends on reducing the formation rate of PbBr64− octahedra and the diffusion rate of MA. The formation of PbBr64− is a rate‐determining step, and the biphasic system offers a favorable reaction condition to control the mass transfer of MA. The effects of temperature and concentration of precursor and ligand are investigated in detail. [ABSTRACT FROM AUTHOR]

Current technological advances and prolific endeavors have entrenched two‐dimensional conducting polymers as the rapidly emerging interface across a diversity of functional materials for flexible electronics, sensors, ion‐exchange membranes, biotechnology, catalysis, energy storage, and conversion. Rational design and fabrication of polymeric nanostructures enriched with well‐ordered geometry are appealing and endorse significant impact on their in‐built electrical, optical, and mechanical properties. In particular, recent interest in controlled hierarchical assembly of monomers/oligomers proved the free‐standing sheet‐like structures with exotic features of high conductivity and flexibility. Yet, the ongoing research to make nanometer‐thick polymers suffers from limitations to access large‐area, mechanical stability, and high‐range internal ordering. In this perspective, we focus on the radical approaches that highlight confinement‐entitled features of two‐dimensional polymeric materials correlating to their interface or template‐assisted synthesis, structure–property relationship, charge transport properties, and future scopes for relevant practical enactments. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1169–1176 [ABSTRACT FROM AUTHOR]

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Freestanding nanopapers were fabricated by the assembly of metal–organic frameworks (MOFs) onto cellulose nanofibers (CNFs). The CNFs are wrapped by continuously nucleated MOF layers (CNF@MOF) by interfacial synthesis, with the charge density on the surface of the CNFs and the dosage of the surfactant polyvinylpyrrolidone (PVP) being carefully adjusted. The obtained CNF@MOF nanofibers with long‐range, continuous, hybrid nanostructures were very different to the composites formed by aggregation of MOF nanoparticles on the substrates. Four typical MOFs (HKUST‐1, Al‐MIL‐53, Zn‐MOF‐74, ZIF‐CO3‐1) were successfully grown onto CNFs in aqueous solutions and further fabricated into freestanding nanopapers. Because of their unique nanostructures and morphologies, the corresponding flexible nanopapers exhibit hierarchical meso‐micropores, high optical transparency, high thermal stability, and high mechanical strength. A proof‐of‐concept study shows that the CNF@MOF nanopapers can be used as efficient filters to separate volatile organic compounds (VOCs) from the air. This work provides a new path for structuring MOF materials that may boost their practical application. Freestanding nanopapers are herein fabricated for the first time by the assembly of metal–organic frameworks wrapping on cellulose nanofibers (see figure). The nanopapers exhibit hierarchical meso‐ and micropores, high optical transparency, excellent mechanical strength, flexibility, and high thermal stability. They may find use as efficient filters for separating volatile organic compounds. [ABSTRACT FROM AUTHOR]

Abstract Biofuels separation using membranes becomes one of the research focuses in the field of renewable energy. In this study, a series of mixed matrix membranes (MMMs) with defect-free active layer around 1 µm thickness were elaborately prepared through interfacial synthesis for ethanol permselective pervaporation. Polydimethylsiloxane (PDMS) was employed as polymer matrix, which adjusted the nucleation of MOF precursors to in situ generate ZIF-8 nanoparticles. Within the active layer, the resultant ZIF-8 nanoparticles provided the preferential pathways for ethanol due to their ultrahigh adsorption capacity and super-hydrophobicity. Moderate aggregation could form the relatively continuous diffusion pathways. This approach rendered the uniform dispersion of ZIF-8 nanoparticles within PDMS matrix and their excellent compatibility. The ZIF-8 nanoparticles endowed the membranes with enhanced ethanol affinity, hydrophobic property, and thermal stability. More importantly, the ZIF-8 nanoparticles substantially reduced the permeation energy barriers of the membrane for penetrants. The membranes displayed the simultaneous increase in permeation flux and separation factor when utilized for ethanol recovery from aqueous solution, revealing the desirable anti-tradeoff effect. Particularly, the resultant membrane exhibited a superior pervaporation performance with relatively high permeation flux (1778 g · m-2 · h-1) and comparable separation factor (12.1) in separating 5.0 wt% ethanol aqueous solution at 40 °C. Graphical abstract fx1 Highlights • Mixed matrix active layer around 1 µm thickness prepared via interfacial synthesis. • Uniformly dispersed ZIF-8 nanoparticles were in situ formed within PDMS matrix. • ZIF-8 nanoparticles created the preferential paths for ethanol rather than for water. • Introducing ZIF-8 nanoparticles addressed facilely trade-off effect in PV membrane. • ZIF-8 nanoparticles notably reduced the permeation energy barriers for penetrants. [ABSTRACT FROM AUTHOR]

Periodic and nanoporous monolayer polymers, the structures of which can be viewed as molecular fishing nets, have been classified as 2D polymers. They have been previously synthesized under mild photoirradiation conditions in the interior of layered single crystals of well‐designed monomers, followed by a liquid‐phase exfoliation. While these mild conditions allow for full structure control, the size of 2D polymers obtained cannot exceed that of the crystals from which they are prepared. In this Review, we discuss different concepts currently pursued to prepare macroscopically sized 2D polymers, focusing on syntheses at the air–water and liquid–liquid interfaces. While these interfaces are larger reaction loci than single crystals, sheet‐like polymers obtained at them pose complex and time‐consuming analytical challenges. Some of these challenges are concretely discussed and indicators are provided for identifying the promising cases, enabling to concentrate on them in the future research. Additionally, this Review discusses three representative examples of 2D polymers to provide a state‐of‐the‐art picture of this emerging field of polymer and materials science. Finally, we sketch the range of applications, such as nanomembranes, electronics, optoelectronics, and electrocatalysts for water splitting, that are relevant for these novel organic 2D materials. From single crystals to monolayers at the air–water interface is a current trend in the synthesis of 2D polymers. This Review explains the advantages and downsides faced when attempting to form 500 000 chemical bonds in a controlled fashion within a single polymer sheet. Recent cases are used to address structural, chemical, and analytical challenges associated with such an endeavor. The manifold applications expected for 2D polymers are the motivation to enter into this exciting field. [ABSTRACT FROM AUTHOR]

Abstract: Metal–organic framework (MOF) membranes are attracting numerous attentions recently. However, fabrication of ultrathin and precisely molecular sieving MOF membranes, especially with highly processable polymeric hollow fiber substrates, is a great challenge. Here, the defect‐free ZIF‐8 composite hollow fiber membranes with impressive performance for hydrogen permselectivity are fabricated by novel interfacial contra‐diffusion synthesis. The reduced graphene oxide (rGO) membranes with good selectivity are prepared on hollow fiber substrates via hydrothermal treatment. By employing the prepared rGO membranes as sharp interfaces to promote the heterogeneous nucleation and control the diffusion of precursors, the ultrathin and uniform MOF membranes with thickness of 150 nm can be regionally crystallized at interfaces by contra‐diffusion synthesis. The prepared ZIF‐8/rGO composite membranes display outstanding separation performance in H2 purification, with permeance over 60 × 10−8 mol m−2 s−1 Pa−1 and H2/CO2, H2/N2 and H2/CH4 selectivities up to 25.3, 70.4, and 90.7, respectively. Moreover, the membranes thus prepared have good reproducibility and long‐term stability. [ABSTRACT FROM AUTHOR]

It is usually difficult to control the microstructure of mesoporous silica materials using coal fly ash as raw materials. In this study, amidoxime-functionalized mesoporous silica nanospheres (ami-MSN) were prepared from coal fly ash using a novel interfacial cohydrolysis-condensation method in an alkane-aqueous system. Characterizations suggested a regular microstructure, high specific surface area (676 m 2 /g) as well as stable and uniformly distributed amidoxime groups in the ami-MSN framework. Furthermore, ami-MSN displays a high U(VI) removal capacity in sorption experiments (98.9% removal efficiency of 50 ppm U(VI) at a dosage of 600 mg/L). The sorption showed significant pH dependence. Introducing various cations and anions showed differing effects on sorption, which can be attributed to differing complexation abilities of ions/ami-MSN/U(VI). The sorption mechanism was also studied. In pursuit of the strategy of “treating wastewater with materials derived from waste,” this work suggests that ami-MSN can be an effective and low-cost sorbent for U(VI) removal. [ABSTRACT FROM AUTHOR]

Abstract: New mechanisms for the controlled growth of one‐dimensional (1D) metal–organic framework (MOF) nano‐ and superstructures under size‐confinement and surface‐directing effects have been discovered. Through applying interfacial synthesis templated by track‐etched polycarbonate (PCTE) membranes, congruent polycrystalline zeolitic imidazolate framework‐8 (ZIF‐8) solid nanorods and hollow nanotubes were found to form within 100 nm membrane pores, while single crystalline ZIF‐8 nanowires grew inside 30 nm pores, all of which possess large aspect ratios up to 60 and show preferential crystal orientation with the {100} planes aligned parallel to the long axis of the pore. Our findings provide a generalizable method for controlling size, morphology, and lattice orientation of MOF nanomaterials. [ABSTRACT FROM AUTHOR]

Synthetic two-dimensional (2D) polymers have totally different topology structures compared with traditional linear or branched polymers. The peculiar 2D structures bring superior properties. Although, from linear to 2D polymers, the study of these new materials is still in its infancy, they already show potential applications especially in optoelectronics, membranes, energy storage and catalysis, etc. In this review, we summarize the recent progress of the 2D materials from three respects: (1) Chemistry--different types of polymerization reactions or supramolecular assembly to construct the 2D networks were described; (2) Preparation methods--surface science, crystal engineering approaches and solution synthesis were introduced; (3) Functionalization and some early applications. [ABSTRACT FROM AUTHOR]

Covalent organic polymers (COPs) with abundant micropores are deemed as promising materials for building molecular separation membranes. In spite of this potential, fabricating COP separation membranes through an efficient and scalable method remains a significant challenge. Herein, we report a simple and efficient strategy for the synthesis of COP membranes with three-dimensionally interconnected micropores. Utilizing transition-metal nitrates as a catalyst, we achieve fast polymerization of amorphous COPs with relatively uniform micropores (0.7 nm in diameter). The rational design of organic-aqueous interface allows for the direct fabrication of robust COP membranes with an ultrathin thickness of ∼20 nm on porous polyacrylonitrile substrates. The resulting hydrophobic but pore-uniform frameworks in these membranes permit fast permeation of organic liquids with a notable molecular weight cutoff of 388 g mol−1 in ethanol. To demonstrate scalability, we show that our strategy can produce large-size COP membranes with a prominent area of 200 cm2, which exhibit performances similar to that of small membrane coupons. The present study offers a potentially scalable method for producing highly microporous COP membranes toward efficient molecular separation in organic liquids. [Display omitted] • A three-dimensional COP with uniform and subnanometer pores is synthesized. • Ultrathin COP membranes are rapidly prepared at ambient conditions. • The optimal COP membrane shows high selectivities with decent solvent permeances. • We produce large-size COP membranes without losing their separation performance. [ABSTRACT FROM AUTHOR]

Supramolecular hydrogels are expected to have applications as novel soft materials in various fields owing to their designable functional properties. Herein, we developed an in situ synthesis of supramolecular hydrogelators, which can trigger gelation of an aqueous solution without the need for temperature change. This was achieved by mixing two precursors, which induced the synthesis of a supramolecular gelator and its instantaneous self-assembly into nanofibers. We then performed the in situ synthesis of this supramolecular gelator at an oil/water interface to produce nanofibers that covered the surfaces of the oil droplets (nanofiber-stabilized oil droplets). External stimuli induced fusion of the droplets owing to disassembly of the gelator molecules. Finally, we demonstrated that this stimuli-induced droplet fusion triggered a synthetic reaction within the droplets. This means that the confined nanofiber-stabilized droplets can be utilized as stimuli-responsive microreactors. [ABSTRACT FROM AUTHOR]

Inspired by the traditional RO membrane fabrication method of interfacial polymerization, ZIF-8 membranes were synthesized on porous polyethersulfone supports based on a liquid–liquid interfacial coordination mechanism. ZIF-8 precursors, zinc nitrate and 2-methylimidazole were dissolved in two immiscible solvents, i.e. water and octanol respectively. The support membrane was first saturated with the aqueous zinc nitrate, followed by pouring an octanol based 2-methylimidazole solution on the surface. After a certain reaction time, a selective MOF layer was formed on the porous polymeric support. XRD patterns combined with ATR-IR results and the SEM images of the synthesized membrane confirmed the formation of a continuous ZIF-8 layer, with selectivities in nanofiltration range, indicating the selective role of the ZIF-8 layer. In this work, the influences of synthesis conditions on the ZIF-8 membrane were investigated in detail, including reaction time, precursor concentrations and support effect. The results showed that dense supports, higher mole ratios of 2-methylimizaole to zinc nitrate and higher 2-methylimizaole concentrations led to denser ZIF-8 membranes with less defects. [ABSTRACT FROM AUTHOR]

Recently, metal-organic frameworks (MOFs) with multifunctional pore chemistry have been intensively investigated for positioning the desired morphology at specific locations onto substrates for manufacturing devices. Herein, we develop a micro-confined interfacial synthesis (MIS) approach for fabrication of a variety of free-standing MOF superstructures with desired shapes. This approach for engineering MOFs provides three key features: 1) in situ synthesis of various free-standing MOF superstructures with controlled compositions, shape, and thickness using a mold membrane; 2) adding magnetic functionality into MOF superstructures by loading with Fe3O4 nanoparticles; 3) transferring the synthesized MOF superstructural array on to flat or curved surface of various substrates. The MIS route with versatile potential opens the door for a number of new perspectives in various applications. [ABSTRACT FROM AUTHOR]

The copper nanoclusters (CuNCs) offer excellent potential as functional biological probes due to their unique photoluminescence (PL) properties. Herein, CuNCs capped with hyperbranched polyethylenimine (PEI) were prepared by the interfacial etching approach. The resultant PEI-CuNCs exhibited good dispersion and strong fluorescence with high quantum yields (QYs, up to 7.5%), which would be endowed for bioimaging system. By changing the reaction temperatures from 25 to 150 °C, the size of PEI-CuNCs changed from 1.8 to 3.5 nm, and thus tunable PL were achieved, which was confirmed by transmission electron microscopy (TEM) imagings and PL spectra. Besides, PEI-CuNCs had smart absorption characteristics that the color changes from colorless to blue with changing the pH value from 2.0 to 13.2, and thus they could be used as color indicator for pH detection. In addition, the PEI-CuNCs exhibited good biocompatibility and low cytotoxicity to 293T cells through MTT assay. Owing to the positively charged of PEI-CuNCs surface, they had the ability to capture DNA, and the PEI-CuNCs/DNA complexes could get access to cells for efficient gene expression. Armed with these attractive properties, the synthesized PEI-CuNCs are quite promising in biological applications. [ABSTRACT FROM AUTHOR]

Metal organic frameworks are an attractive platform to develop fascinating electrocatalysts for the oxidation of ascorbic acid (AA), and their different morphologies have been hinted in literature to impact their sensing performance. In this work, by varying the reaction medium of metal source and organic ligand, copper 2-hydroxybenzene-1,4-dicarboxylate (CuBDC-OH) nanosheets (NSs), nanorods (NRs) and bulk were generated. Thereinto, CuBDC-OH-NSs displayed the highest sensitivity of 151.99 μ A mM -1 cm -2 in the linear range of 12-1074 μ M, which is 1.5 times greater than that of CuBDC-OH NRs and 3.5 times greater than that of CuBDC-OH bulk. The electrochemical analyzes manifested that the superiority of nanosheets originated from higher oxidative current, larger electrochemical active surface area and lower charge transfer resistance, which enabling the efficient electro-oxidation of AA. Additionally, satisfactory selectivity, stability and reproducibility were obtained., (© 2023 IOP Publishing Ltd.)