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Phosphanes play an important role in various applications, serving as a class of organic bases with basicities spanning more than 30 orders of magnitude. Accessing comprehensive basicity data for phosphanes has been challenging due to scattered information across multiple sources and notable gaps in the existing data. In this report, we present basicities (pKaH values) of a diverse set of phosphanes, both newly measured or calculated and collected from the literature. We demonstrate that pKaH values can serve as an alternative to Tolman electronic parameters (TEP values) in evaluating the electronic properties of phosphanes. Additionally, we suggest parameters for assessing the steric properties of phosphanes without the need for preparation or calculation of metal-ligand complexes. [ABSTRACT FROM AUTHOR]

The utilization of resins combined with nanoparticles represents the prevailing method for fabricating superhydrophobic fabrics. Nevertheless, a notable drawback in this approach has been the limited durability of these fabrics, constraining their practical applications. In our ground-breaking study, we introduce an innovative and reliable solution to address this durability issue. We demonstrate, for the first time, that biopolymer resins offer a significantly enhanced level of durability to superhydrophobic fabrics when compared to their synthetic counterparts, whether organic or inorganic. Our proposed method employs the dip-coating technique, enabling us to create fabrics capable of maintaining their anti-wetting properties even in the face of mechanical stress. The deposition of this coating on the fabric surface elevates the water contact angle to an impressive 157°, with a sliding angle measuring below 10°. In terms of oils, the fabric surface exhibits superoleophilic behavior, with a contact angle of 0°. Furthermore, our coating exhibits outstanding thermal stability, enduring temperatures of up to 250 °C, while also demonstrating UV resistance for up to 50 hours without any loss of superhydrophobicity. Mechanical stability was also assessed, and the coating proved resilient against abrasion until the appearance of tears on the fabric, without compromising its superhydrophobic properties. Our coated fabric has been effectively employed in separating oil/water mixtures, achieving an exceptional separation efficiency of 99%, a performance that remains consistent across multiple cycles. We envision that these superhydrophobic/superoleophilic fabrics, characterized by their cost-effectiveness, eco-friendliness, remarkable durability, and ease of industrial scale application, hold immense potential for applications in clothing manufacturing and water/oil separation. [ABSTRACT FROM AUTHOR]

Electrochemical catalysts for the oxygen evolution reaction (OER) with abundant reserves, high catalytic activity, and robust stability are highly crucial for efficient electrocatalytic water splitting. Herein, we designed and synthesized non-noble metal coordinated porphyrin-based hypercrosslinked polymers (FX-M-TPP), which were characterized by SEM, TEM, and XPS. Their performance as electrocatalysts for OER was evaluated in 1 M KOH, among which FX-FeCo-TPP exhibited a minimum overpotential of 251 mV at 10 mA cm−2, with a Tafel slope of 35.2 mV dec−1 demonstrating excellent stability. By studying the intermediates in the OER process, it was revealed that the true catalytically active substances are metal hydroxides that evolved from FX-FeCo-TPP. The results of this work provide a new method for designing high-performance OER catalytic materials based on organic compounds. [ABSTRACT FROM AUTHOR]

Copper ions (Cu2+) play an essential role in various cellular functions, including respiration, nerve conduction, tissue maturation, oxidative stress defense, and iron metabolism. Covalent organic frameworks (COFs) are a class of porous crystalline materials with directed structural designability and high stability due to the combination of different monomers through covalent bonds. In this study, we synthesized a porphyrin-tetrathiazole COF (TT-COF(Zn)) with Zn-porphyrin and tetrathiafulvalene (TTF) as monomers and used it as a photoactive material. The strong light absorption of metalloporphyrin and the electron-rich properties of supplied TTF contribute to its photoelectrochemical performance. Additionally, the sulfur (S) in the TTF can coordinate with Cu2+. Based on these properties, we constructed a highly sensitive photoelectrochemical sensor for detecting Cu2+. The sensor exhibited a linear range from 0.5 nM to 500 nM (R2 = 0.9983) and a detection limit of 0.15 nM for Cu2+. Notably, the sensor performed well when detecting Cu2+ in water samples. [ABSTRACT FROM AUTHOR]

A solvent extraction method was improved using organic bases such as triethylamine (Et3N) that neutralize HCl effectively and stabilize sol–gel derivative alumina frameworks as insoluble species, thereby achieving removal of EOnPOmEOn at a rate higher than 90% to obtain high-quality mesoporous alumina. [ABSTRACT FROM AUTHOR]

Morpholine motifs have been used extensively as targeting moieties for lysosomes, primarily in fluorescence imaging agents. Traditionally these imaging agents are based on organic molecules which have several shortcomings including small Stokes shifts, short emission lifetimes, and susceptibility to photobleaching. To explore alternative lysosome targeting imaging agents we have used a rhenium based phosphorescent platform which has been previously demonstrated to have an improved Stokes shift, a long lifetime emission, and is highly photostable. Rhenium complexes containing morpholine substituted ligands were designed to accumulate in acidic compartments. Two of the three complexes prepared exhibited bright emission in cells, when incubated at low concentrations (20 μM) and were non-toxic at concentrations as high as 100 μM, making them suitable for live cell imaging. We show that the rhenium complexes are amenable to chemical modification and that the morpholine targeted derivatives can be used for live cell confocal fluorescence imaging of endosomes–lysosomes. [ABSTRACT FROM AUTHOR]

Crystalline porous organic salts (CPOSs), formed by the self-assembly of organic acids and organic bases through ionic bonding, possess definite structures and permanent porosity and have rapidly emerged as an important class of porous organic materials in recent years. By rationally designing and controlling tectons, acidity/basicity (pKa), and topology, stable CPOSs with permanent porosity can be efficiently constructed. The characteristics of ionic bonds, charge-separated highly polar nano-confined channels, and permanent porosity endow CPOSs with unique physicochemical properties, offering extensive research opportunities for exploring their functionalities and application scenarios. In this review, we systematically summarize the latest progress in CPOS research, describe the synthetic strategies for synthesizing CPOSs, delineate their structural characteristics, and highlight the differences between CPOSs and hydrogen-bonded organic frameworks (HOFs). Furthermore, we provide an overview of the potential applications of CPOSs in areas such as negative linear compression (NLC), proton conduction, rapid transport of CO2, selective and rapid transport of K+ ions, atmospheric water harvesting (AWH), gas sorption, molecular rotors, fluorescence modulation, room-temperature phosphorescence (RTP) and catalysis. Finally, the challenges and future perspectives of CPOSs are presented. [ABSTRACT FROM AUTHOR]

The properties of functional materials based on organic π-conjugated systems are governed extensively by intermolecular interactions between π-molecules. To establish clear relationships between supramolecular structures and functional properties, it is essential to attain structurally well-defined π-stacks, particularly in solution, as this enables the collection of valuable spectroscopic data. However, precise control and fine-tuning of π-stacks pose significant challenges due to the weak and bidirectional nature of π–π stacking interactions. This article introduces the concept of "frustrated π-stacking," strategically balancing attractive (π–π interaction) and repulsive (steric hindrance) forces in self-assembly to exert control over the sizes, sequences of π-stacks, and slip-stacked structures. These research efforts contribute to a deeper understanding of the correlation between π-stacks and their properties, thereby providing useful insights for the development of molecular materials with the desired performance. [ABSTRACT FROM AUTHOR]

Two organic ligands, one rigid and one flexible, were designed and used to construct two cobalt-based metal–organic frameworks (MOFs) with coligands to obtain 3D and 2D structures, respectively. Both the Co-based MOFs were pyrolyzed at different temperatures to obtain the derived materials, and their electrocatalytic hydrogen evolution properties were studied. The results show that the electrocatalytic hydrogen evolution performance of MOF derivatives based on the rigid ligand was better than that of MOF derivatives based on the flexible organic ligand. [ABSTRACT FROM AUTHOR]

Recent years have seen dramatic improvements in the design of organic fluorophores based on limiting non-radiative decay pathways. We sought to extend this understanding to benzothiadiazoles that have been used as turn-on fluorescent substrates for the self-labeling protein HaloTag. When conjugated to HaloTag, the benzothiadiazoles reside in a narrow tunnel that precludes twisted internal charge transfer, which allowed us to explore steric and electronic effects on other non-radiative decay pathways. By minimizing both non-radiative decay and nonspecific interactions with cellular components, we produced improved turn-on dyes with 136-fold increase in fluorescence over background in cells. [ABSTRACT FROM AUTHOR]

Electroactive organic materials have received much attention as alternative electrodes for metal–ion batteries due to their high theoretical capacity, resource availability, and environmental friendliness. In particular, redox-active covalent organic frameworks (COFs) have recently emerged as promising electrodes due to their tunable electrochemical properties, insolubility in electrolytes, and structural versatility. In this Highlight, we review some recent strategies to improve the energy density and power density of COF electrodes for lithium batteries from the perspective of molecular design and electrode optimisation. Some other aspects such as stability and scalability are also discussed. Finally, the main challenges to improve their performance and future prospects for COF-based organic batteries are highlighted. [ABSTRACT FROM AUTHOR]

Traditional water-soluble organic macrocyclic receptors generally lack photofunctionality, thus monitoring the drug delivery and the phototheranostic applications of these host–guest macrocyclic systems has been greatly restricted. To address this issue, incorporating π-conjugated dye chromophores as building blocks into macrocyclic molecules is a straightforward and promising strategy. This approach not only imparts intrinsic optical features to the macrocycles themselves but also enhances the host–guest binding ability due to the large planar structures of the dyes. In this feature article, we focus on recent advances in water-soluble macrocyclic compounds based on organic dye chromophores, such as naphthalimide (NDI), perylene diimides (PDI), azobenzene (azo), tetraphenylethylene (TPE) and anthracene, and provide an overview of their various applications including molecular recognition, drug release, biological imaging, photothermal therapy, etc. We hope that this article could be helpful and instructive for the design of water-soluble dye-based macrocycles and the further development of their biomedical applications, particularly in combination with drug therapy and phototheranostics. [ABSTRACT FROM AUTHOR]

A substantial number of works have focused on the identification and classification of high explosives and organic compounds based on nanosecond laser-induced plasma spectroscopy (LIPS), but the major spectral differences between different molecular solids are still not well understood. The objective of this work is to determine the spectral regions that are most discriminatory of each material using chemometrics. Five high explosives and five organics containing benzene rings are measured in an air environment using nanosecond LIPS. Six different regions of the spectrum are subsequently obtained using a six-channel spectrometer, and then k-means clustering analysis in two-dimensional principal component space is used for each wavelength band to reveal the greatest spectral disparities. It is speculated that more carbon atoms in the functional groups tend to participate in the formation of the C2 emission, while the carbon in the carbon ring tends to contribute more to the formation of the CN emission. Additionally, the quantitative correlations between C2 emission intensity, oxygen balance (OB), and aroma index are also clarified for the first time. Finally, well-performing classification models are established using well-chosen spectral features with a supervised quadratic discriminant classifier (QDC) and linear support vector machine (SVM) with both specificity and accuracy of above 99%. This work proposes that nanosecond LIPS can be used as a chemical probe to detect structural discrepancies among organic samples and thus distinguish them well. [ABSTRACT FROM AUTHOR]

Two-dimensional metal–organic framework nanosheets are attractive as peroxidase mimicking nanocatalysts due to their rich chemical functional groups, large surface area, high porosity, and accessible active sites. In this study, we synthesized FeCu bifunctional 2D MOF nanosheets using a solvothermal method. Fe and Cu ions were added as metal precursors, while organic amine and acid served as the organic ligands to construct the FeCu-MOF nanosheets. These nanosheets demonstrated robust peroxidase-like catalytic activities and were employed to develop a visual detection system for multiple targets, such as glucose and kanamycin. In the detection mechanism, glucose was oxidized into gluconic acid by glucose oxidase (GOx), leading to the generation of H2O2. When H2O2 is present, the FeCu-MOF NSs demonstrate high intrinsic peroxidase-like activity, which might catalytically oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) into a blue-coloured oxTMB product with a strong UV absorption at 654 nm. Subsequently, kanamycin was added to the above sensing system. The kanamycin strongly interacted with the FeCu-MOF NSs through H-bonding and blocked electron transfer, resulting in a colour change of the solution from blue to colourless with a weak UV absorption at 654 nm. Under the optimal conditions, the proposed colorimetric sensor exhibits an excellent linear response to glucose and kanamycin over the 0.25–5 μM and 0.02–0.1 μM ranges, respectively. The proposed colorimetric assay detection limits for glucose and kanamycin were found to be as low as 0.1 μM and 8 nM, respectively, and such a sensor shows excellent selectivity and sensitivity against different potential interferents. Thus, our proposed colorimetric assay was satisfactory when applied to glucose and kanamycin detection in agricultural and livestock husbandry samples. [ABSTRACT FROM AUTHOR]

Solution-processed organic photovoltaics (OPVs) is one of the most promising photovoltaic technologies in the energy field, due to their clean and renewable low-cost manufacturing potential. OPV has rapidly developed with the design and synthesis of highly efficient photovoltaic materials and the development of smart device engineering. To date, the majority of advanced OPV devices have been prepared using halogenated solvents, achieving power conversion efficiencies (PCE) exceeding 19% on a laboratory scale. However, for industrial-scale production, less toxic manufacturing processes and environmental sustainability are the key considerations. Therefore, this review summarizes recent advances in green solvent-based approaches for the preparation of OPVs, highlighting material design (including polymer donors and small molecule acceptors) and device engineering (co-solvent methods, additive strategies, post-treatment methods, and regulation of coating method), emphasizing crucial factors for achieving high performance in green solvent-processed OPV devices. This review presents potential future directions for green solvent-based OPVs, which may pave the way for future industrial development. [ABSTRACT FROM AUTHOR]

In order to balance the contradiction between mesopore introduction and loss of microporosity, a surface modification strategy is proposed by selectively adsorbing organic alkaline molecules on Beta molecular sieves before NaOH etching. Organic alkaline molecules adsorb on framework aluminum sites and the protective function of organic bases is affected by the adsorption configuration and physical barrier effect of organic bases. Organic alkaline molecules serve as a protective agent to increase the bond length of Al-O bonds. Therefore, the as-synthesized hierarchical Beta molecular sieves have more acid sites due to the preservation of aluminum atoms. When employed as catalysts in the dehydration reaction of glucose, 5-hydroxymethylfurfural (5-HMF) is obtained under the synergistic effect of Brønsted and Lewis acid sites. The unique contribution is to realize the porosity regulation and alleviate the acidity loss of Beta molecular sieves. These results are important to broaden the application fields of aluminum-silicon molecular sieves especially for large molecule-engaged acid catalyzed reactions. [ABSTRACT FROM AUTHOR]

Innovative design of smart organic materials is of great importance for the advancement of modern technology. Macrocycle hosts, possessing cyclic skeletons, intrinsic cavities, and specific guest binding properties, have demonstrated pronounced potential for the elaborate fabrication of a variety of functional organic materials with smart stimuli-responsive characteristics. In this tutorial review, we outline the current development of smart organic materials based on macrocycle hosts as key building blocks, focusing on the design principles and functional mechanisms of the tailored systems. Three main types of macrocycle-based smart organic materials are exemplified as follows according to the distinct forms of construction patterns: (1) supramolecular polymeric materials and nanoassemblies; (2) adaptive molecular crystals; (3) smart porous organic materials. The responsive performances of macrocycle-containing smart materials in versatile aspects, including mechanically adaptive polymers, soft optoelectronic devices, data encryption, drug delivery systems, artificial transmembrane channels, crystalline-state gas adsorption/separation, and fluorescence sensing, are illustrated by discussing the representative studies as paradigms, where the roles of macrocycles in these systems are highlighted. We also provide in the conclusion part the perspectives and remaining challenges in this burgeoning field. [ABSTRACT FROM AUTHOR]

Small-molecule (SM) donor based ternary organic solar cells (OSCs) have drawn increasing attention owing to the remarkable photovoltaic performances achieved recently. In this study, a chlorinated benzodithiophene core and selenophene-containing π bridge based SM donor, namely CBTSeHR, was used as an SM donor guest to fabricate ternary OSCs owing to its favorable optoelectronic properties. CBTSeHR exhibits a good complementary absorption band and matched energy levels with the prevailing polymer donors and SM nonfullerene acceptors (NFAs), which is beneficial to light harvesting and charge transport. In addition, the incorporation of CBTSeHR could modulate the micro morphology and endow the ternary blend with more favorable phase separation size. Accordingly, the as cast ternary device prepared by introducing CBTSeHR into the D18:CH-6F host system exhibits an excellent power conversion efficiency (PCE) of 17.33%, which is even higher than that of the optimal binary host device (17.08%). After thermal annealing (TA) treatment, an outstanding PCE value of 18.41% with a high Voc of 0.901 V, FF of 0.767, and Jsc of 26.64 mA cm−2 was achieved, demonstrating the great success of SM donor based ternary OSCs. [ABSTRACT FROM AUTHOR]

Room temperature phosphorescence (RTP) using pure organic compounds is highly desirable for a wide variety of applications in the optical electronics and biological fields. Herein, we studied the RTP properties of a few star-shaped pure organic molecules based on carbazole and chalcogen atoms using quantum chemical methods. The calculated intersystem crossing (ISC) rate constant is found to be ∼108–10 s−1 for these molecules. The ISC and efficiency of RTP are increased by incorporating a heavy halogen atom, which is facilitated by strong SOC. In contrast to the traditional organometallic phosphors used in OLEDs, this study illustrates the rational molecular design of metal-free organic room-temperature phosphorescent emitters containing chalcogen and halogen atoms. [ABSTRACT FROM AUTHOR]

We report on the design of 1D MOFs based on a nopinane-annelated organic ligand and Co(II) or Ni(II), the variation of which allows tuning the optical modulation bandwidth. Structural and time-resolved analysis revealed the optical modulation mechanism, the rates and its endurance, thereby enriching the list of sustainable MOFs for tunable optical modulators. [ABSTRACT FROM AUTHOR]

Herein, a novel rocking-chair aqueous AIB, based on the Ni-PBA inorganic cathode and PTO organic anode, is presented. This device showed an excellent cycle life and high efficiency, endowed with a high capacity-retention of 96.0% and coulombic efficiency (CE) of over 99% at 1 A g−1 after 5000 cycles. The environmentally friendly and ultralong-life aqueous AIBs are expected to provide new options for next-generation energy storage devices. [ABSTRACT FROM AUTHOR]

A self-assembled ambipolar organic semiconductor based on naphthalene diimide with low clearing temperature, solution processability, and high molar extinction coefficient, exhibiting a room temperature columnar hexagonal liquid crystalline phase is reported. [ABSTRACT FROM AUTHOR]

Heteroepitaxial growth and alloys with novel physicochemical properties are attracting great attention in the photoelectric field, and inorganic heteroepitaxial growth and inorganic alloys have been well controlled via changing experimental conditions. Meanwhile, organic heterostructures (OHSs) and organic alloys (OAs) are less studied due to strict requirements for lattice parameters. Moreover, the occurrence of organic homogeneous nucleation is another main problem to solve in OHSs and OAs. Herein, by taking advantage of the similarity between N＝N and C＝C, we present a cocrystal strategy to maintain the molecular arrangement and lattice parameters, and perfect lattice matching is realized in the case of mutual substitution of N＝N and C＝C in molecules. Furthermore, we successfully achieved perfect organic heteroepitaxy and organic alloys with the same materials. We expect the realization of more versatile OHSs and OAs by introducing N＝N and C＝C into the photoelectric field. [ABSTRACT FROM AUTHOR]

Fluorine-containing materials have enriched the field of molecular and cellular MRI with unambiguous and quantitative detection capabilities. The background-free "hot-spot" display and the large range of chemical shifts of the broad palette of 19F-formulations are now used for a variety of applications. The common features of these formulations are: (i) they are based on organic molecular backbones (i.e., organofluorines); and (ii) their 19F-MRI detectability relies on a well-defined and clearly observed 19F-MR signal. During the last few years, our lab aimed to expand the 19F-MR toolbox with new capabilities that were, thus far, not used in molecular and cellular 19F-MRI. This Feature Article summarizes our developments and implementations in the field of 19F-MRI emphasizing (i) the introduction of ultrasmall inorganic fluoride-based nanocrystals (nanofluorides) as nano-sized (<10 nm) agents for 19F-MRI, and (ii) the use of Chemical Exchange Saturation Transfer (CEST) in the 19F-MRI framework to indirectly amplify 19F-MR signals of otherwise-undetected fluorinated entities. [ABSTRACT FROM AUTHOR]

Organic room-temperature phosphorescence (RTP) materials are currently the focus of research in the field of bioimaging. In comparison with the conventional imaging modalities based on organic fluorescent dyes, RTP materials with long lifetime enable time-resolved imaging to improve the imaging resolution by avoiding autofluorescence. In this review, we will start with summarizing strategies for achieving high performance RTP materials for bioimaging, including the development of RTP-compounds, host–guest doping materials, and supramolecular assemblies. We then discuss the optimization of nanonization processes to obtain RTP nanoparticles with controllable size, high dispersibility, and improved stability. The differences between top-down and bottom-up approaches are further described. Finally, we briefly introduce the emerging methods for preparing RTP materials for bioimaging. [ABSTRACT FROM AUTHOR]

Two charge-transfer cocrystals using 1,4,5,8-naphthalenetetracarboxylic diimide derivatives (NDIs) as donor block and coronene as acceptor segment were synthesized through solution centrifugation and investigated as cathode electrodes in lithium-ion batteries (LIBs). These cocrystals showed 1 : 1 mixed stacking with columnar structure, good thermal stability, and narrow band gaps of 2.24 eV or 2.34 eV. V ia alkyl terminal tuning, methyl-NDI based complex (CN-1) displayed lower binding ability than propyl substituted complex (CN-3) and could undergo a crystal transition into a new solvent-free phase with void-rich architecture. LIB based CN-1 cocrystal as cathode electrode showed a specific capacity of up to 230 mA h g−1 with long cyclability over 600 cycles due to its unique void-rich columnar and deformable structure. The lithiation and delithiation sites on aromatic backbones were testified by experimental and calculated results. This study thus not only provides a novel kind of organic cathode material but also proves that donor–acceptor complexes are promising candidates for the development of high-performance cathodes for LIBs. [ABSTRACT FROM AUTHOR]

Herein, the in situ N-alkylation between tripyridine molecules and C2H5OH was employed to obtain four iodometallates (Mn+ = Pb2+, Cu+ and Ag+). Among them, the alkylation degree of the tripyridine molecules is different, and the in situ-generated tripyridine derivatives showed different configurations. This is not only related to the structure of the inorganic anions but also related to the tripyridine molecule itself. The two moieties were actually templates for each other. The Pb2+ compound 1 was found to effectively catalyze the degradation of Rhodamine B (RhB), with its degradation efficiency reaching 94% in 70 min. In contrast, the degradation efficiency for the Cu+ and Ag+ compounds 2–4 did not exceed 50%. The free radical trapping test indicated that with the Pb2+ compound as the photocatalyst, both superoxide ion radicals (˙O2−) and holes (h+) played a key role. Alternatively, with compound 3 or 4 as the photocatalyst, only ˙O2− played a role. The differences should be related to the band gap of the materials, where the Pb2+ compound has a slightly wider band gap, leading to a higher exciton separation efficiency. Due to the involvement of more free radicals, the usual intermediates did not appear in the catalytic process of 1, while the colored species appeared in the catalytic process of 3 and 4. The cyclic test verified that compound 1 still had high catalytic activity after recycling five times. Also, we investigated the catalytic capacity of 1 for the degradation of 5-times the quantity of RhB. The degradation rate reached 99% in 5.5 hours, indicating that 1 has a good photocatalytic performance for degrading a high concentration of RhB. However, given that the amount of catalyst and dye used in each study was different, it was difficult to compare the results. Thus, herein, we introduced for the first time the method of calculating the TOF value to better evaluate the photodegradation performance of each hybrid material. [ABSTRACT FROM AUTHOR]

The mechanisms of Cu(II)/DBU-catalyzed carboxylation of homopropargylic amines with CO2 to construct 6-methylene-1,3-oxazin-2-ones are studied via density functional theory. The calculations suggest that Cu(II) catalysts exhibit a positive effect on the process of intramolecular cyclization, and the catalytic activities of which are determined by their coordination abilities ((DBU)CuCl2 < CuCl2 < [(DBU)CuCl]+). Furthermore, three roles of DBU are revealed in this study: (a) DBU acts as the proton-acceptor to capture a proton of homopropargylic amines. (b) DBU attacks CO2 to form DBU-CO2 as the nucleophilic agent, and then DBU-CO2 assists the H+ shift as the proton shuttle. (c) DBU serves as the ligand replacing one Cl− anion of CuCl2, forming the activated species [(DBU)CuCl]+. Besides, the theoretical study well explains the selectivity of Cu(II)-catalyzed reactions (6- vs. 7-membered cyclization), and the 6-membered products are found to be formed selectively. Overall, our work reproduces the experimental results well and provides an indispensable understanding of CO2-conversion to synthesize various high-value chemicals with the assistance of a catalytic system combining transition-metal catalysts and organic bases. [ABSTRACT FROM AUTHOR]

Mn metal batteries are rarely reported due to the lack of a stable electrolyte. Here, an N,N-dimethylformamide (DMF)-based organic electrolyte with stable Mn plating/stripping for over 500 h and high Coulombic efficiency (CE) for a Mn metal battery is presented. The battery—specifically composed of an electrolyte made of DMF and ethylenediamine (EDA), a cathode made of 3,4,9,10-perylenetetracarboxylicdiimide (PTCDI), and an anode made of Mn metal—displayed a specific capacity of 105 mA h g−1. These results indicated the effectiveness of our new method for preparing low-cost and highly stable secondary Mn ion batteries. [ABSTRACT FROM AUTHOR]

A three-dimensional metal–covalent organic framework (3D-MCOF) based on cyclic trinuclear units was synthesized using organic tetrahedral linkers and copper-based cyclic trinuclear complexes. The novel type of 3D-MCOF, named 3D-CTU-MCOF, with the ctn topology, is reported herein for the first time. Our study demonstrated enhanced electrocatalytic capacity for CO2 reduction reaction of 3D-CTU-MCOF compared to independent cyclic trinuclear units. [ABSTRACT FROM AUTHOR]

Conjugated-polymer-based donor–acceptor hybrid nanostructures have been the subject of great interest, mainly due to their potential applications in photovoltaic and other electronic and optoelectronic devices. Here, we have demonstrated a different aspect of these hybrid nanostructures toward efficient photocatalysis in an aqueous medium. The hybrid donor–acceptor nanostructures were prepared by assembling a carboxylic acid-functionalized fullerene molecule (phenyl C-61 butyric acid) (PCBA) on the surface of an amine-functionalized regioregular P3HT nanostructure through acid–base interaction. The efficient photoinduced charge separation and charge transfer in the hybrid material were investigated by steady-state and time-resolved photoluminescence and photocurrent measurements. The photocatalytic activity of the hybrid nanostructure in water under visible light irradiation (using a 20 W white LED bulb) was investigated, and it was found to show 82.5% dye degradation efficiency. To facilitate the reusability of the photocatalyst, a membrane-based dip-photocatalyst was developed from this material, and it shows 87.5% dye degradation efficiency and can be reused multiple times without a significant change in degradation efficiency. [ABSTRACT FROM AUTHOR]

In this paper, a series of donor–π–acceptor (D–π–A) type oligomers were investigated for their structural and electronic properties through density functional theory (DFT) and time dependent-DFT (TD-DFT) calculations. The designed compounds consist of five different donor units linked at the ortho position of the perylene core of the perylene diimide (PDI) acceptor via five different π-bridging units. We have calculated the dihedral angle, average inter-ring bridge bond distance (l), inter-ring torsional angle (φ), distortion energy (ΔEdis), bond length alteration (BLA) parameter (Δr), energy band gap (ΔH–L) values, partial density of states (PDOS), ionization potential (IP), electron affinity (EA), molecular electrostatic potential surface (MEPS) analysis, transition dipole moment, reorganization energy (λ), electronic coupling matrix element (V), charge transfer rates (kCT), hopping mobility (μhop), electron density difference (EDD), natural transition orbital (NTO) and spectral absorption properties of the studied compounds. The MEPS plots suggest that the studied compounds have significant charge transport properties. From the EDD map analysis, it is clear that the Sg → S1 transition involves greater charge transfer from the donor to the acceptor unit via the π-bridging unit in all compounds. Further, the NTO analysis confirms the transfer of electron density from the donor to the acceptor unit after electronic excitation of the compounds. We have also studied the absorption and photovoltaic properties of the D/A blends by considering KM-10 as a standard donor and C60-CN as a standard acceptor. The study suggests that complex KM-10/PDI-BITHN-4 with a theoretical PCE of 19.26% can be chosen as the potential candidate for application in organic solar cells (OSCs). Thus, our study provides recommendations for further development of efficient D/A complexes so as to improve the performance of OSCs. [ABSTRACT FROM AUTHOR]

A porphyrin containing covalent organic framework (COF) was developed as the glutathione responsive nitric oxide (NO) donor delivery nanoplatform for "1 + 1 > 2" synergistic cancer therapy of NO mediated therapy and photodynamic therapy. [ABSTRACT FROM AUTHOR]

A new luminescent hybrid material with dual-emission centers (Eu@Dye@TpDq hydrogel) based on a covalent organic framework (COF) has been successfully prepared. First, we designed a dye (coumarin) modified COF (TpDq) hybrid fluorescent material (Dye@TpDq), and then the material was formed into a hydrogel film, with an Eu3+ ion being introduced as another luminescent center into the material during the cross-linking process. As a dual-emission fluorescent platform, it exhibits a double-response towards different heavy metal ions: a ratiometric identification response to Cu(II), and a turn-off fluorescence response to Cr(VI). This research not only introduces a novel synthesis of Eu3+-functionalized double emitting COF-based hydrogels, but also inspires the development of COF-based multifunctional analytical tools. [ABSTRACT FROM AUTHOR]

Phosphate based organic polymer networks (OPNs) have been synthesized for the first time for dye sorption and heterogeneous catalysis. The OPNs were sythesized by the polycondensation of POCl3 with di- and tri-hydroxy organic linkers e.g., quinol, 4,4′-biphenol, phloroglucinol and 1,3,5-(4-hydroxyphenyl)benzene. These show remarkably selective adsorption of cationic dyes methylene blue and propidium iodide via the electrostatic interaction of the polymers with the dyes. These OPNs also allow the in situ synthesis and stabilization of gold nanoparticles within the polymer networks which demonstrate effective heterogeneous, catalytic reduction of the aromatic nitro to amino group. [ABSTRACT FROM AUTHOR]

Flash (extremely fast) electrochemical generation of unstable arylbis(arylthio)sulfonium triflates [ArS(ArSSAr)]+ [OTf]− that are unsuitable for accumulation in batch processes was achieved within 10 s in a divided-type flow electrochemcial reactor, enabling one-flow access to vinyl triflates, short-lived oxocarbenium triflates and glycosyl triflates. [ABSTRACT FROM AUTHOR]

BINOL moieties of different electronic demand are useful blocks for enabling the photo-production and modulation of triplet excited states in readily-accesible BINOL-based O-BODIPY dyes from standard F-BODIPY precursors. The rapid and rational development of smarter triplet-enabling BODIPY dyes on the basis of this strategy (e.g., TADF biomarker 4a or room temperature phosphor 4g) paves the way for advancing photonic applications based on organic triplet photosensitizers. [ABSTRACT FROM AUTHOR]

Metal catalysts have always been used in the aerobic oxidation of hydroquinones to benzoquinones. Here an organic base was used as a catalyst to carry out this reaction in the presence of molecular oxygen, which produces hydrogen peroxide (H2O2) as the by-product under metal-free conditions. Various bases, reaction times, temperatures, and solvents were examined, along with the scope of the reaction. The relationship between the dissociation constant (pKa) values of different organic bases and the conversion of hydroquinones was studied. The effects of water on this reaction were also observed. It is shown that the role of the base in the reaction process is to promote proton transfer from hydroquinones, which is exacerbated by the protic nature of the solvent. The results of mechanistic studies suggested that this reaction probably occurs via an ionic pathway. This simple base-catalyzed aerobic oxidation provides a green alternative for the manufacture of benzoquinones from hydroquinones. [ABSTRACT FROM AUTHOR]

A hierarchical nanoreactor based on covalent organic frameworks (COFs) was fabricated using polystyrene spheres (PSs) as a template. When applied in cascade catalysis, the nanoreactor significantly improved the catalytic activity of internal enzymes, and showed protection for the enzyme in harsh environments. Moreover, glucose can be sensitively detected (detection sensitivity: 10 μM) by the nanoreactor. [ABSTRACT FROM AUTHOR]

A mild and efficient photocatalytic C–H bond activation strategy has been developed based on organic small molecules. A combination of the excellent redox-active activity of the pyridinium unit and Brønsted basic site of the N-heterocyclic unit offers a concerted pathway for H abstraction through concomitant proton and electron transfer, thus solving the key dehydrogenation process of C–H bond activation. The photocatalytic system shows high performance in selective oxidation of ethylbenzene, toluene and its homologue, and a gram-level conversion of p-xylene into terephthalic acid has been achieved at room temperature under an air atmosphere without any co-catalysts and additives. [ABSTRACT FROM AUTHOR]

An organic cocrystal based on pyrene and tetrachloroterephthalonitrile is reported in this work. The cocrystal exhibits both elastic and controllable and defectless cutting postprocess properties. The mechanism of postprocessing was studied via comparative study, nanoindentation and theoretical calculations in detail. [ABSTRACT FROM AUTHOR]

An iterative step-growth addition method was used to expedite the gram-scale synthesis of main-chain polyviologens by several days, while also producing the longest main-chain polyviologen (i.e., 26 viologen subunits) reported to date. Facile degradation using inorganic and organic aqueous bases was also demonstrated for a representative oligoviologen (6V-Me·12Cl), a polyviologen (26V-Me·52Cl), and oligoviologen-crosslinked hydrogels. [ABSTRACT FROM AUTHOR]

We report an efficient and economical amidation strategy by using a polyoxometalate-based iron catalyst that affords the corresponding amide products in good yields. All of the aliphatic, aromatic and heterocyclic substrates are produced in high yields without additional base or organic ligands. Most importantly, the first example of heterogeneous iron(III)-catalyzed formation of the diamides is developed. [ABSTRACT FROM AUTHOR]

The present work describes the first visible light-assisted, metal-free and organic base 1,1,3,3-tetramethyl guanidine (TMG) mediated synthesis of unsymmetrical methyl aryl/alkyl carbonates from the reaction of alcohols, methanol, and CO2 in high to excellent yields under atmospheric pressure and ambient temperature conditions. [ABSTRACT FROM AUTHOR]

In view of Hg2+ ion sensing by luminescence, a series of new, phenanthroline-decorated 3D lanthanide metal organic frameworks (Ln-MOFs) valorising an original combination of four different lanthanides and two organic ligands, i.e. thiobis(4-methylene-benzoic acid) (H2tmba) and 1,10-phenanthroline (phen), have been successfully synthesized, namely {[Ln4(tmba)6(phen)4]·m(H2O)(phen)}n [Ln = Ce, m = 3 (1); Pr, m = 1 (2); Eu, m = 3 (3); and Tb, m = 3 (4)]. Compounds 1–4 were characterised by single-crystal X-ray diffraction, elemental and thermogravimetric analyses, and powder X-ray diffraction. The luminescence properties of complexes 3 and 4 were thoroughly investigated. It is herein proved that compound 3 sensitively and selectively acts as an excellent luminescent probe for the detection of Hg2+ ions in waters, with a detection limit of 1.00 μM. As additional assets, 3 displays superb stability over a wide pH range (3–12) of the aqueous media, as well as convenient recycling after completion of the detection experiments. The rationale for the observed luminescence quenching effect of mercury might be a strong interaction arising between Hg2+ ions and the carboxylate oxygen atoms of the tmba2− ligand. The results open new perspectives for applications in environmental remediation. [ABSTRACT FROM AUTHOR]

In this study, we introduced four "claw-like" units of dipicolylamine (DPA) to a tetraphenylethylene (TPE)-based organic molecular cage (DPA-TPE-Cage). Coordinated with Zn2+ ions, the obtained ZnDPA-TPE-Cage exhibited aggregation induced emission (AIE) effects and oxidase-like properties, which endowed it with the ability to selectively image and kill Gram-positive bacteria S. aureus efficiently. [ABSTRACT FROM AUTHOR]

In situ monitoring of the location and transportation of bioactive molecules is essential for deciphering diverse biological events in the field of biomedicine. In addition, obtaining the in situ information of lesions will provide a clear perspective for surgeons to perform precise resection in clinical surgery. Notably, delivering drugs or operating photodynamic therapy/photothermal therapy in situ by labeling the lesion regions of interest can improve treatment and reduce side effects in vivo. In various advanced imaging and therapy modalities, optical theranostic agents based on organic small molecules can be conveniently modified as needed and can be easily internalized into cells/lesions in a non-invasive manner, which are prerequisites for in situ bioimaging and precision treatment. In this tutorial review, we first summarize the in situ molecular immobilization strategies to retain small-molecule agents inside cells/lesions to prevent their diffusion in living organisms. Emphasis will be focused on introducing the application of these strategies for in situ imaging of biomolecules and precision treatment, particularly pertaining to why targeting therapy in situ is required. [ABSTRACT FROM AUTHOR]

The construction of three-dimensional (3D) covalent organic frameworks (COFs), especially fully conjugated 3D COFs, is a long-standing challenge. Herein, we report a saddle-like, π-conjugated cyclooctatetrathiophene (COTh) as a tetrahedral node to construct fully conjugated 3D COFs. The present work enriches the structural diversities and potential applications of 3D COFs. [ABSTRACT FROM AUTHOR]

Here, we present a 4-nitrophenyl functionalized Zr-UiO-66 MOF (MOF = metal--organic framework) and its applications towards the selective, sensitive and rapid detection of H2S both in the aqueous medium and vapour phase. The MOF material was synthesized using the 2-(nitrophenoxy)terepththalic acid (H2BDC-O-Ph-NO2) linker and ZrCl4 salt in the presence of a benzoic acid modulator. It was carefully characterized by thermogravimetric analysis (TGA), elemental analysis, powder X-ray diffraction (PXRD), FT-IR spectroscopy and surface area analysis. Noticeable thermal stability up to a temperature of 390 °C under air and the considerable chemical stability in different liquid media (H2O, 1 M HCl, glacial acetic acid, NaOH in the pH = 8 to 10 range) confirmed the robustness of the MOF. The BET surface area (1040 m² g-1) indicated the porous nature of the MOF. Remarkable selectivity of the MOF towards H2S over other potential congeners of H2S was observed in the aqueous medium. A very high fluorescence increment (~77 fold) was observed after adding an aqueous Na2S solution to the MOF suspension. The MOF probe displayed the lowest limit of detection (12.58 nM) among the existing MOF-based chemosensors of H2S. Furthermore, it exhibited a very quick (60 s) response towards H2S detection. The MOF compound could also detect H2S in the vapour phase as well as in real water samples. Furthermore, we developed inexpensive MOF-coated paper strips for the naked-eye sensing of H2S. A thorough investigation was carried out in order to elucidate the fluorescence turn-on sensing mechanism. [ABSTRACT FROM AUTHOR]

Three kinds of microstructures were prepared for one organic phosphor based on a solution-concentration-controlled self-assembly strategy. These microstructures show different phosphorescence efficiencies, which holds considerable promise for the miniaturized optical device applications of ultralong organic phosphorescence materials. [ABSTRACT FROM AUTHOR]