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A benzofuran-[ b ]-fused BODIPY trimer has been efficiently synthesized, featuring a unique structural design that harmoniously integrates TBET (through bond energy transfer) and PET (photo-induced electron transfer) mechanisms. This trimer boasts exceptional optical properties, including a large pseudo-Stokes shift of 100 nm, an impressive fluorescence quantum yield ( Φ FL = 0.931), an outstandingly high extinction coefficient (182 100 M -1 cm -1 ), a remarkable FEF (fluorescence enhancement factors, 22.4-fold) values as well as exhibiting AIE (aggregation-induced emission) activity, and has been successfully utilized in two-photon fluorescence imaging of live-cell lipid droplets.

To design an efficient, low-cost, and easily recoverable oxygen evolution reaction (OER) electrocatalyst, this work focuses on two-dimensional vdW ferromagnetic Cr 2 Ge 2 Te 6 . Based on the density functional theory (DFT) calculations, the adsorption of oxygen-containing intermediates during the OER process will gradually decrease the bandgap of Cr 2 Ge 2 Te 6 , thus increasing its electrical conductivity. More importantly, we propose a two active sites synergistic mechanism through a hydroxyl-boosted pathway. With the combined action of the two active sites, the binding between the oxygen-containing intermediates and the surfaces is enhanced. The enhancement comes from dramatic charge-transfer-induced Te-3p and O-2p orbital enhancement. As a result, the overpotential of the OER reduces from 1.25 to 0.59 V. We hope these findings will pave the way for more experimental and theoretical research to explore the potential applications of two-dimensional vdW ferromagnetic materials in energy storage and conversion.

Three new distinct NIR α,α-NH-bridged BODIPY dimers were prepared by a direct nucleophilic substitution reaction. The synergistic effects of the nitrogen bridges and strong excitonic coupling between each BODIPY unit play major roles in enhancing the delocalization of an electron spin over the entire BODIPY dimers. The in situ formed aminyl radical dimer showed an absorption maximum at 1040 nm.

Due to the advantages of good aqueous dispersion and biocompatibility, carbon dots (CDs) are promising candidates for a wide range of applications in the biological field. Notably, CDs derived from biosafe organic precursors will contribute both new types of CDs and new bioactivities. Herein, metformin (MET), a first-line drug for the treatment of type II diabetes, was selected as an organic precursor to fabricate a new type of CDs, namely, semi-carbonized MET (MCDs). These MCDs derived from MET possess a completely new antibacterial activity against Staphylococcus aureus ( SA ) and Escherichia coli ( E. coli ) compared with that of MET and achieve complete antibacterial activity at 200 μg mL -1 . The broad-spectrum antibacterial mechanism of MCDs involves two aspects. For the Gram-positive bacteria SA , MCDs mainly affect the transport of nutrients by adsorbing onto the surface of bacteria, thereby inhibiting bacterial growth. For the Gram-negative bacteria E. coli , MCDs can easily pass through their thin cell walls and stimulate the bacteria to produce excess ROS, eventually leading to the death of the bacteria. This work may open a new way for the future design and development of CDs prepared from biosafe organic precursors with specific functions.

The carbon emission problem is a significant challenge in today's society, which has led to severe global climate issues. Membrane-based separation technology has gained considerable interest in CO 2 separation due to its simplicity, environmental friendliness, and energy efficiency. Crystalline porous materials (CPMs), such as zeolites, metal-organic frameworks, covalent organic frameworks, hydrogen-bonded organic frameworks, and porous organic cages, hold great promise for advanced CO 2 separation membranes because of their ordered and customizable pore structures. However, the preparation of defect-free and large-area crystalline porous material (CPM)-based membranes remains challenging, limiting their practical use in CO 2 separation. To address this challenge, the solution-processing method, commonly employed in commercial polymer preparation, has been adapted for CPM membranes in recent years. Nanosheets, spheres, molecular cages, and even organic monomers, depending on the CPM type, are dissolved in suitable solvents and processed into continuous membranes for CO 2 separation. This feature article provides an overview of the recent advancements in the solution processing of CPM membranes. It summarizes the differences among the solution-processing methods used for forming various CPM membranes, highlighting the key factors for achieving continuous membranes. The article also summarizes and discusses the CO 2 separation performance of these membranes. Furthermore, it addresses the current issues and proposes future research directions in this field. Overall, this feature article aims to shed light on the development of solution-processing techniques for CPM membranes, facilitating their practical application in CO 2 separation.

The hydrogen oxidation reaction is an important process in anion exchange membrane fuel cells with alkaline solutions. The pursuit of efficient catalysts for alkaline hydrogen oxidation has attracted considerable attention. In this study, we present a precursor route for the synthesis of a new Ir-based catalyst (Ir-Ni/NiO/C), in which Ir nanoclusters were immobilized on the generated Ni/NiO/C support derived from a metal-organic framework. The small size of Ir clusters facilitates the exposure of catalytically active sites. The electronic interplay between the Ir nanoclusters and the Ni/NiO/C support optimized the hydrogen binding energy (HBE) and hydroxide binding energy (OHBE) on the surface, which is unattainable on the contrasting Ir-C, Ir-Ni/C, and Ir-NiO/C products. The optimized catalyst shows excellent mass activity for alkaline hydrogen oxidation, which is 3.1 times that of the Pt/C catalyst. This study presents a promising pathway for the development of advanced HOR catalysts.

Ordered M 1 Zn 1 intermetallic phases with structurally isolated atom sites offer unique electronic and geometric structures for catalytic applications, but lack reliable industrial synthesis methods that avoid forming a disordered alloy with ill-defined composition. We developed a facile strategy for preparing well-defined M 1 Zn 1 intermetallic nanoparticle (i-NP) catalysts from physical mixtures of monometallic M/SiO 2 (M = Rh, Pd, Pt) and ZnO. The Rh 1 Zn 1 i-NPs with structurally isolated Rh atom sites had a high intrinsic selectivity to ethylene (91%) with extremely low C 4 and oligomer formation, outperforming the reported intermetallic and alloy catalysts in acetylene semihydrogenation. Further studies revealed that the M 1 Zn 1 phases were formed in situ in a reducing atmosphere at 400 °C by a Zn atom emitting-trapping-ordering (Zn-ETO) mechanism, which ensures the high phase-purity of i-NPs. This study provides a scalable and practical solution for further exploration of Zn-based intermetallic phases and a new strategy for designing Zn-containing catalysts., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Reversible thermochromism presents depth at low temperatures and brightness at high temperatures, which is not conducive to the application of the passive energy-saving and shading effect. Here, we propose an innovative strategy for unconventional reversible thermochromic energy-storage flexible wood films (FT-PCMs-2) by the contribution of polyvinyl alcohol/propylene glycol (PVA/PG). Upon heating, the FT-PCMs-2 changes from light red/green to dark red/green, in contrast to the color change of the non-flexible composites without PVA/PG. The FT-PCMs-2 has good flexibility, mechanical strength and thermal stability. Among them, MSR-DEW-6PVA and MSG-DEW-6PVA have better comprehensive properties, including suitable phase change temperatures (38.6 °C and 37.2 °C), high latent heat values (59.79 J g -1 and 73.02 J g -1 ), and low supercooling degrees (2 °C and 0.6 °C). FTIR, XRD and SEM analysis show that the binary fatty acid eutectics were successfully loaded into the eucalyptus fibre skeleton with physical interaction with PVA/PG. In addition, MSR-DEW-6PVA and MSG-DEW-6PVA have photothermal conversion rates of 48.3% and 36%, good cycling stability and anti-leakage performance after 50 cycles, and have promising applications in the fields of building energy saving, intelligent windows and decoration., Competing Interests: No conflict of interest exits in the submission of this manuscript., (This journal is © The Royal Society of Chemistry.)

The integration of high activity, selectivity and stability in one electrocatalyst is highly desirable for electrochemical CO 2 reduction (ECR), yet it is still a knotty issue. The unique electronic properties of high-nuclear clusters may bring about extraordinary catalytic performance; however, construction of a high-nuclear structure for ECR remains a challenging task. In this work, a family of calix[8]arene-protected bismuth-oxo clusters (BiOCs), including Bi 4 (BiOC-1/2), Bi 8 Al (BiOC-3), Bi 20 (BiOC-4), Bi 24 (BiOC-5) and Bi 40 Mo 2 (BiOC-6), were prepared and used as robust and efficient ECR catalysts. The Bi 40 Mo 2 cluster in BiOC-6 is the largest metal-oxo cluster encapsulated by calix[8]arenes. As an electrocatalyst, BiOC-5 exhibited outstanding electrochemical stability and 97% Faraday efficiency for formate production at a low potential of -0.95 V vs. RHE, together with a high turnover frequency of up to 405.7 h -1 . Theoretical calculations reveal that large-scale electron delocalization of BiOCs is achieved, which promotes structural stability and effectively decreases the energy barrier of rate-determining *OCHO generation. This work provides a new perspective for the design of stable high-nuclear clusters for efficient electrocatalytic CO 2 conversion., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Design and fabrication of cost-effective (pre-)catalysts are important for water splitting and metal-air batteries. In this direction, various metal-organic frameworks (MOFs) have been investigated as pre-catalysts for oxygen evolution. However, the activation process and the complex reconstruction behaviour of these MOFs are not well understood. Herein, square-like MOF nanosheets in which carbon nanotubes were embedded were prepared by introducing an amine ligand to coordinate with Ni ions and then reacting with [Fe(CN) 6 ] 3- . The formed MOF nanosheets containing nickel and iron species were then activated by NaBH 4 , inducing the leaching of ligands and the formation of tiny active species in situ loaded on carbon nanotubes. The prepared catalyst shows superior oxygen evolution performance with an ultralow overpotential of 231 mV for 10 mA cm -2 , a fast reaction kinetics with a small Tafel slope of 52.3 mV dec -1 , and outstanding catalysis stability. The excellent electrocatalytic performance for oxygen evolution can be attributed to the structural advantage of in situ derived small sized active species and one-dimensional conductive networks. This work provides a new thought for the enhancement of the electrocatalytic performance of MOF materials.

Two-dimensional hydrogen boride (HB) sheets prepared via the ion-exchange reaction from magnesium diboride (MgB 2 ) are known to possess several intriguing properties for a wide range of applications; however, previous reports have shown that the sheets prepared using this method contain small amounts of reactive components, making them unsuitable for certain applications. Therefore, developing a method for preparing HB sheets that exhibit long-term stability and do not contain reactive species is essential. In this study, we developed an effective treatment method for achieving long-term stabilization of HB sheets. We found that by pre-treating the HB sheets with water and then filtering the dried product from an acetonitrile dispersion, we could achieve excellent long-term stability over nine months. This stability was maintained even outside of a glovebox, with no H 2 released by the decomposition and/or reaction. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) absorption spectroscopy measurements revealed that the sample exhibited pure HB characteristics with negatively charged boron and B-H-B and terminal B-H bonds, even after nine months of storage. Furthermore, based on thermal desorption spectroscopy (TDS) measurements, the presence of reactive species in the as-prepared HB sheets is attributed to fluctuating B-H bonds with relatively weak binding energies that can be removed using the method developed in this study.

Lead halide perovskite nanocrystals possess incredible potential as next generation emitters due to their stellar set of optoelectronic properties. Unfortunately, their instability towards many ambient conditions and reliance on batch processing hinder their widespread utilities. Herein, we address both challenges by continuously synthesizing highly stable perovskite nanocrystals via integrating star-like block copolymer nanoreactors into a house-built flow reactor. Perovskite nanocrystals manufactured in this strategy display significantly enhanced colloidal, UV, and thermal stabilities over those synthesized with conventional ligands. Such scaling up of highly stable perovskite nanocrystals represents an important step towards their eventual use in many practical applications in optoelectronic materials and devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A twisted dumbbell-like chiral superstructure can be easily assembled in aragonite under the co-action of CTAB and Mg 2+ , producing a microstructure that is very similar to that of Turritella terebra shell. Asymmetric adsorption of the CTAB head group on aragonite, namely "adsorption chirality", is the reason for the chiral assembly.

The development of hydrogen-oxygen fuel cells with an alkaline electrolyte was highly limited by the sluggish kinetics of the hydrogen oxidation reaction (HOR). Here, with a pyrolysis-reduction route, a new RuNi-based electrocatalyst was prepared, which presents an ultrathin nanowire-like structure. In alkaline media, this catalyst shows an excellent catalytic performance with an exchange current density of 1.10 mA cm -2 disk for hydrogen oxidation. The exchange current density and mass activity of this catalyst are much higher than those of its single-metal counterparts and even the commercial Pt/C catalyst containing 20% Pt. Such a remarkable catalytic activity can be explained by the interaction between Ru and Ni; the incorporation of Ni may induce an electronic effect on the optimization of the Ru-H ad strength and provide a functional surface that can absorb OH species, thus boosting the catalytic activity. These findings may cast a new light on the exploration of low-cost but high-efficiency catalysts for fuel cells.

The rapid development of modern medicine has put forward new requirements for wound infection healing methods in clinical treatment. Despite the great achievements made in the research and development of various types of dressings in recent years, yet there is still a challenge of multifunctional dressings for effective wound treatment. Herein, a multifunctional nanofibrous membrane was prepared by encapsulating NIR-adsorbed CuS (FSC/CuS) nanoparticles, polyvinylpyrrolidone (PVP) and polyvinyl butyral (PVB) with electrospun fish scale collagen. During the evaluation of wound healing, four parameters, including hemostasis time, inflammatory response, cell proliferation, and tissue remodeling, were considered. The results of H&E, Masson and immunohistochemical staining showed that the synergistic effect of composite nanofibers and near-infrared light can inhibit the inflammatory response, promote the proliferation and migration of fibroblasts and keratinocytes, rebuild new tissues, form well-dispersed collagen fibers, etc . It was shown that the FSC/CuS NPs combined with an NIR-driven experimental group exhibited excellent performance in accelerating wound healing in these stages. This kind of nanofibrous scaffold prepared with fish scale and NIR-absorbing agents will have broad application prospects in the healing of infected wounds.

Injected steam can be converted to the sub/supercritical state during the in situ exploitation of oil shale. Thus, the pyrolysis behavior and pyrolysate characteristic of Fushun oil shale during anhydrous pyrolysis and sub/supercritical water pyrolysis were fully compared. The results revealed that the discharged oil yields from sub/supercritical water pyrolysis were 5.44 and 14.33 times that from anhydrous pyrolysis at 360 °C and 450 °C, which was due to the extraction and driving effect of sub/supercritical water. Also, sub/supercritical water could facilitate the discharge and migration of shale oil from the pores and channels. The H 2 and CO 2 yields in sub/supercritical water pyrolysis were higher than that in anhydrous pyrolysis, resulting from the water-gas shift reaction. The component of shale oil was dominated by saturated hydrocarbons in anhydrous pyrolysis, which accounted for 50-65%. In contrast, a large amount of asphaltenes and resins was formed during pyrolysis in sub/supercritical water due to the solvent effect and weak thermal cracking. The shale oil from anhydrous pyrolysis was lighter than that from sub/supercritical water pyrolysis. Sub/supercritical water reduced the geochemical characteristic indices and lowered the hydrocarbon generation potential and maturity of solid residuals, which can be attributed to the fact that more organic matter was depolymerized and released. The pyrolysate characteristic of oil shale in sub/supercritical water pyrolysis was controlled by multiple mechanisms, including solvent and driving effect, chemical hydrogen-donation and acid-base catalysis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Dietary protein is crucial for maintaining body growth and plays a significant role in shaping the gut microbiota. Rice bran (RB) rancidity can induce rice bran protein (RBP) oxidation and change the structural characteristics, which further impacts the functional properties and nutritional value of RBP. Therefore, the impact of rancidity-induced RBP oxidation on the gut microbiota and intestinal permeability was evaluated. Oxidized RBP significantly altered the α-diversity of the gut microbiota and impacted the microbial profile at phylum and genus levels, and moderately oxidized RBP caused increasing abundance of Akkermansia and reducing abundance of Desulfovibrio . Different oxidation extents of RBP induced different biomarkers, indicating that the composition of the gut microbiota presented an oxidation extent-dependent pattern. Oxidized RBP also significantly promoted the level of formic acid and reduced the level of isovaleric acid. Moreover, oxidized RBP significantly upregulated the expression of genes related to tight junction proteins. The phenomena indicated that oxidized RBP significantly changed the composition of the gut microbiota and improved the barrier function of the intestine, while showing fewer effects on the production of short-chain fatty acids (SCFAs). The research provides a theoretical reference for understanding the effects of plant protein oxidation on intestinal health during food storage and processing.

For the first time, a novel class of deep-blue (DB)-emitting Cs x (NH 4 ) 1- x PbCl 2 Br (0.3 ≤ x ≤ 1) perovskite nanocrystals (PNCs) were prepared by a facile ligand-assisted one-step ball milling method. The resulted PNCs are characterized by high chlorine content (66.7%) and excellent color purity. Their photoluminescence position can be finely modulated from 434 nm to 447 nm, which extends notably beyond the current Rec. 2020 color standard, by the NH 4 + content. Among them, Cs 0.3 (NH 4 ) 0.7 PbCl 2 Br shows the highest quantum yield close to 40%. The PNCs exhibit high phase and optical stability under ambient conditions and UV light according to the NH 4 + content. This work offers a new avenue to produce DB perovskites for future full-color displays and optoelectronics.

The cationic surfactant-lipid interaction directs the development of novel types of nanodrugs or nanocarriers. The membrane action of cationic surfactants also has a wide range of applications. In this work, combining a photo-voltage transient method with the traditional dynamic giant unilamellar vesicle (GUV) leakage assay and molecular dynamics (MD) simulations, we monitored the molecular actions of a representative cationic surfactant, tetradecyl trimethyl ammonium bromide (TTAB), in a wide concentration range ( i.e. , 0.5 μM-10 mM), on a phospholipid bilayer membrane in real time. With low concentrations ( e.g. , ≤10 μM), TTAB performed a three-stage acting process, including the structural-disturbance-dominated, adsorption-dominated, and dynamic equilibrium stages. At higher concentrations ( e.g. , ≥100 μM), this process was accelerated to two stages. Furthermore, TTAB induced deformation and even rupture of the membrane, due to the asymmetric disturbance of surfactant molecules on the two leaflets of a bilayer. All these disturbances induced membrane permeabilization, and the times at which these transitions occurred are given. This work provides information on time and molecular mechanism during the membrane actions of cationic surfactants, and provides a simple and real-time method in studying the dynamic processes at the membrane interface.

It is a challenge to effectively load proton carriers in COFs to improve their proton conductivity. Herein, we report a series of COF-based composites, PANa@UCOF- x (PANa: sodium polyacrylate, x : weight percentage of PANa), which were prepared by coating different proportions of superabsorbent PANa on the COF surface based on an in situ reaction strategy. Since PANa can greatly enhance the enrichment of water molecules in one-dimensional (1D) channels of COFs, these COF-based composites exhibit superprotonic conduction. At 80 °C and 95% relative humidity (RH), the proton conductivity of PANa@UCOF-10, PANa@UCOF-28 and PANa@UCOF-40 reaches 1.6 × 10 -2 , 5.1 × 10 -2 , and 1.1 × 10 -1 S cm -1 , respectively, which is 4-5 orders of magnitude higher than 7.4 × 10 -7 S cm -1 of the original UCOF. This work not only develops a new method to improve the water content of the COF channels, but also proves the important role of ordered channels in constructing effective proton conduction pathways.

Pneumonia is a kind of inflammation, which can cause high morbidity and mortality, and the treatment of pneumonia has received widespread attention. Heme oxygenase-1 (HMOX1) is a cell protective enzyme and can generate an anti-inflammatory response. Here, we demonstrate that degradable carbon dots (from L-ascorbic acid, CDs-1) can up-regulate the expression of HMOX1 in animal cells and tissues, which has a therapeutic effect on LPS-induced acute lung injury in mice. It was confirmed from in vitro experiments that CDs-1 could significantly up-regulate the expression of mRNA and the protein of HMOX1, which can increase the expression of HMOX1 by 5 times in a short time, decreasing the reactive oxygen species level in a cellular inflammation model induced by LPS. Furthermore, a series of in vivo comparative experiments show that CDs-1 could effectively treat acute lung injury and improve the survival rate of mice to 80%. Our work provides a practical way for the treatment of acute inflammation and the promising application of CDs in anti-inflammation.

The manufacture of blue light-emitting diodes (LEDs) has always been a tough problem to solve in the display and illumination fields. Inorganic/organic semiconductors and carbon dots (CDs) with a wide band gap still face obstacles such as a low external quantum efficiency (EQE) and poor stability. Herein, we synthesized highly stable and blue emission CDs with a chemically inert surface, and the photoluminescence (PL) peak (in ultra-pure water) of which is located at 446 nm with an absolute PL quantum yield (PLQY) of 26.4%. The LEDs based blue emission CDs exhibit an electroluminescence (EL) peak located at 456 nm and a high brightness of 223 cd m -2 with an EQE of 0.856%. The Commission Internationale del'Eclairage (CIE) coordinates are located at (0.21, 0.23) and the device lifetime with 65% brightness ( T 65 ) reaches over 217 h because of the chemically inert surface of the CDs. The results mean the devices are the most stable CDs-LEDs reported to date. This work represents a novel route for the preparation of low cost, highly stable and very bright CDs-LEDs with a short wavelength emission., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The direct 3,3'-dimerization of BODIPYs lacking substituent groups in the 1,2,6, and 7 positions was developed by oxidative coupling with FeCl 3 . This regioselective dimerization was achieved for BODIPYs substituted only in the 5-position with Cl or aryl groups. Further functionalization of the 5,5'-dichloride dimer gave the corresponding pyrrole or 4-(2-aminoethyl)morpholine disubstituted dimers 2f and 2g, respectively. While dimer 2f exhibited intense NIR absorption/emission maxima at 773/827 nm in toluene, dimer 2g showed favorable lysosome-targeting NIR fluorescence in living cells.

The auxiliary light equipment for plant growth requires phosphor-converted light-emitting-diodes (pc-LEDs) with high luminous efficiency and a stable structure, and the properties of phosphors highly determine the performance of the pc-LEDs. This work reports a deep-red emitting phosphor with an ultra-wide response range which is regarded as CaMgAl 10 O 17 :Mn 4+ . The absorption range spans the ultraviolet, near-ultraviolet, blue, and green light regions from 250 to 550 nm. Under the excitation of the best excitation position at 343 nm, deep-red light at 654 nm is emitted, and the quantum efficiency is as high as 86.7%. The luminous efficiency of the two pc-LED devices prepared based on CaMgAl 10 O 17 :Mn 4+ with 395 and 460 nm chips reached 54.3 and 59.6 lm W -1 , respectively. The spectra of the two pc-LEDs exhibit high resemblance to the absorption spectra of chlorophyll A and B in plant growth photosynthesis. These indicate that the CaMgAl 10 O 17 :Mn 4+ phosphor can be an excellent candidate for plant growth LED light.

A highly efficient cyanosilylation protocol mediated by the easily available n-BuLi with a wide range of aldehydes and ketones was developed. This protocol features excellent yields with very low n-BuLi loadings (0.01-0.05 mol%) at room temperature, solvent-free process, good chemo-/regio-selectivity and functional group tolerance and scalability. A possible reaction pathway based upon stoichiometric reactivity was put forward.

Photodynamic therapy has great potential for tumor ablation and the activation of antitumor immune responses. However, its overall therapeutic efficiency is often limited by the immunosuppressive tumor microenvironment. We developed a near-infrared light-excitable immunomodulating nano-photosensitizer (NeINP) that can improve reactive oxygen species production and regulate the immunosuppressive TME to improve photoimmunotherapy. The NeINP is composed of a photosensitive core and a pH-responsive polymer shell, which allows for NeINP loading and delivery of small-molecular immunomodulators to tumor sites for regulation of the immunosuppressive TME and effective photoimmunotherapy. Through the co-delivery of celecoxib and the NIR-triggered photodynamic core to tumors, the NeINP was shown to regulate the immunosuppressive TME and enhance antitumor immunity, leading to the elimination of residual tumor and reduction of metastasis and recurrence. The NeINP can be optimized to co-deliver other immunomodulators, and thus has potential as a universal platform for efficient, precise photoimmunotherapy.

Among various kinds of materials that have been investigated as electrocatalysts for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), metal-organic frameworks (MOFs) has emerged as a promising material for electrocatalyzing these vital processes owing to their structural merits that integrate advantages of both homogeneous and heterogeneous catalysts; however there is still big room for their improvement in terms of inferior activity and poor conductivity, as well as the ambiguity of real active sites. In this review, advanced strategies with the aim of solving the activity and conductivity problems are summarized as microstructure engineering and conductivity improvement, respectively. The structural evolution of some MOFs and their real active species has also been discussed. Finally, perspectives on the development of MOF materials for HER, OER and ORR electrocatalysis are provided.

Developing new techniques that can synthesize one-dimensional piezoelectric materials on a large scale is of great significance for boosting piezocatalytic applications. In this work, we proposed a high-efficiency template hydrothermal method for large-scale synthesis of piezoelectric Na 0.5 Bi 0.5 TiO 3 (NBT) nanowires. By ion-exchange with Bi 3+ , Na 2 Ti 3 O 7 template nanowires can be easily and entirely transformed to NBT. The piezocatalytic activity of the NBT nanowires was thoroughly investigated with respect to their capability to degrade typical organic pollutants, including Rhodamine B, methylene blue, methyl orange, tetracycline hydrochloride, phenol, and bisphenol A. The NBT nanowires exhibited the highest efficiency in piezocatalytic degradation of Rhodamine B, which was completely decomposed within 80 min (rate constant ∼0.0575 min -1 ). The electron spin resonance spin-trapping technique and active species capture experiments were employed to characterize free radicals. The present work is advantageous for the high yield of NBT nanowires and the excellent piezocatalytic performance. The reported template hydrothermal method can potentially be extended to the synthesis of other perovskite nanowires., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

P-glycoprotein (P-gp), a member of ATP-binding cassette (ABC) transporters, is a multidrug resistance pump. Its promiscuous nature is the main cause of multidrug resistance in cancer cells. P-gp can bind multiple drug molecules simultaneously; however, the binding mechanism is still not clear. Furthermore, the upper limit of the number of substrates that can be accommodated by the binding pocket is not fully understood. In this work, we explore the dynamic process of P-gp binding to multiple substrates by using molecular dynamics (MD) simulations. Our results show that P-gp possesses the ability for simultaneous binding, and that the number of substrates has an upper limit. The accommodating ability of P-gp relates to the size of the binding drugs, and conforms to induced fit theory. In the binding process, the residues 339PHE, 982MET and 986GLN are essential. The pocket of P-gp presents strong flexibility and adaptability features according to the mutation results in this work. Drug molecules tend to gather in the pocket during binding, and interactions between these molecules are beneficial to simultaneous binding. These findings provide new insights into the mechanism of the promiscuous nature of P-gp, and may give us a guideline for inhibiting the process of multidrug resistance.

Gram-positive bacteria are one of the most common pathogens causing severe and acute infection, and hospital infection caused by Gram-positive bacteria have increased significantly. Also, as antibiotics have been widely used, abusing of antibiotics is becoming an increasingly serious problem which is followed by dangerous drug resistance. Here, we developed a series of cationic carbon dots (CDs) with high-performance as antibacterial agents by using tartaric acid and m-aminophenol as precursors. The surface charge of these CDs can be regulated from +4.5 ± 0.42 mV to +33.2 ± 0.99 mV by increasing the contents of pyridine N and pyrrolic N in CDs. Further antibacterial experiments show that 250 μg mL -1 of CDs with +33.2 ± 0.99 mV can selectively kill Gram-positive bacteria and the antibacterial efficiency can reach approximately >99%. These CDs with positive surface charge can be selectively absorbed on the cell walls of Staphylococcus aureus (S. aureus) via electrostatic interaction and then disturb their physiological metabolism, eventually leading to bacterial death. The present work provides a novel method to adjust the surface charge of CDs and apply these CDs as alternative antibacterial agents.

We report the cyclic single-crystal-to-single-crystal transformation of three hydrogen-bonded organic frameworks (HOFs), induced by the change of temperature and humidity, which clearly reveals that the -SO 3 - and -NH 2 groups in UPC-H7 and UPC-H8 facilitate the diffusion of water molecules into their anhydrous structures to form hydrous UPC-H9. Their proton conductivity was studied under different humidity at varying temperature, showing that the proton conductivity is closely related to water molecules entering the crystal structures arising from the hydrogen bonded reorganization in combination with the triaxial single-crystal proton conductivity tests.

Alloying/doping in two-dimensional (2D) materials is emerging as an increasingly important strategy due to the wide-range bandgap tunability and versatility of these materials. Monolayer 2D transition metal dichalcogenide (TMD) alloy has been investigated both theoretically and experimentally in recent years. Here, we synthesized a bilayer MoS 2(1- x ) Se 2 x semiconductor alloy via the chemical-vapor deposition technique. The as-grown triangular MoS 2(1- x ) Se 2 x flakes with size of roughly 10 μm were observed by optical microscope and scanning electron microscope (SEM). The 1.4-1.9 nm thickness of the samples, as measured by AFM, means that bilayer MoS 2(1- x ) Se 2 x alloys were grown. The characteristic Raman modes related to Mo-S and Mo-Se vibrations were observed in the Raman spectrum. Two emission peaks were respectively found, corresponding to the A and B excitons in the photoluminescence (PL) spectrum. XPS measurements confirmed the Se doping of the alloy. The first-principles calculation results show a contraction of the band gap value with the increase of Se doping in the MoS 2 lattice. Compared with monolayer MoS 2(1- x ) Se 2 x alloy, the band bending effect is more obvious, and the bilayer MoS 2(1- x ) Se 2 x alloy still shows the direct band gap luminescence characteristic, which has certain guiding significance for the growth of two-dimensional materials and for device preparation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Since most toxicological risk assessments are based on individual single-species tests, there is uncertainty in extrapolating these results to ecosystem assessments. Herein, we successfully developed a mediated microbial electrochemical biosensor with mixed microorganisms for toxicity detection by microelectrode array (MEA). In order to fully mobilize all the mixed microorganisms to participate in electron transfer to amplify the current signal, 1,4-benzoquinone (BQ) was used as the lipophilic mediator to mediate the intracellular metabolic activities. Hydrophilic K 3 [Fe(CN) 6 ] was employed as an extracellular electron acceptor to transport electrons from hydroquinone (HQ) to the working electrode. Under the optimal conditions of 50 mM phosphate buffer solution (PBS), 0.4 mM BQ, 10 mM K 3 [Fe(CN) 6 ] and OD 600 = 0.5 bacteria concentration, the half-maximal inhibitory concentration (IC 50 ) values measured with the composite-mediated respiration (CM-RES) of BQ-K 3 [Fe(CN) 6 ] for Cu 2+ , Cd 2+ and Zn 2+ were 5.95, 7.12 and 8.86 mg L -1 , respectively. IC 50 values obtained with the single mediator K 3 [Fe(CN) 6 ] were 2.34, 5.88 and 2.42 mg L -1 for the same samples. The results indicate that the biosensor with the single mediator K 3 [Fe(CN) 6 ] had higher sensitivity to heavy metal ions than the biosensor with composite mediators. After verification, we found that the addition of BQ cannot amplify the current. The IC 50 value of 0.89 mg L -1 for BQ was obtained using K 3 [Fe(CN) 6 ] as the single mediator. This suggests that BQ is highly toxic, which explained why the sensitivity of the biosensor with the combined mediator BQ-K 3 [Fe(CN) 6 ] was lower than that of the biosensor with the single mediator K 3 [Fe(CN) 6 ]. At the same time, this also implies that toxicity itself cannot be ignored when it is used as an electronic mediator in a mediated microbial electrochemical biosensor.

A diastereoselective three-component reaction of diazo compounds with alcohols and pyrazolinone ketimines by utilizing rhodium(ii) catalysis via interception of transient oxonium ylides is reported. The reaction provides an efficient approach for the facile construction of polyfunctionalized pyrazolone derivatives bearing two contiguous quaternary stereocenters in good yields with high regioselectivities and excellent diastereoselectivities.

Interfacial adhesion has been identified as being key for realizing flexible devices. Here, strong interfacial nanoconnections involving metallic patterns on polymer surfaces were fabricated via a molecular bonding approach, which includes UV-assisted grafting and molecular self-assembly. The interfacial characteristics of conductive patterns on liquid crystal polymer substrates were observed via transmission electron microscopy and atomic force microscopy infrared spectroscopy. The interfacial molecular layers have a thickness of 10 nm. Due to the successful molecular bonding modifications, interfacial adhesion has been sufficiently improved; in particular, the peel-related breakage sites will be located in the modified layers on the plastic surface beneath the interface after the metallic coatings are peeled off. Integrating X-ray photoelectron spectroscopy, infrared spectroscopy, and scanning electron microscopy results, the molecular bonding mechanism has been revealed: UV-assisted grafting and self-assembly result in the construction of interfacial molecular architectures, which provide nanosized connecting bridges between the metallic patterns and polymer surfaces. Such in-depth interfacial studies can offer insight into interfacial adhesion, which will impact on the development of metal/polymer composite systems and continue to push the improvement of flexible devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Infections caused by Gram-negative bacteria have been an increasing problem worldwide. Meanwhile, the overuse of traditional antibiotics has caused an emergence of drug resistance. The development of new antibacterial agents, which can cope with the threat from drug-resistant bacteria, is urgently needed. Herein, carbon dots (ACDs) derived from Artemisia argyi leaves were obtained via a smoking simulation method and exhibited selective antibacterial ability of targeting Gram-negative bacteria. The bactericidal efficiency of ACDs (150 μg mL-1) for Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Proteusbacillus vulgaris) can reach 100%, while for Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), ACDs have no significant antibacterial function, indicating that the particles can selectively target specific bacteria. The antibacterial mechanism for ACDs confirmed that ACDs could only damage the cell walls of Gram-negative bacteria but not that of Gram-positive bacteria. Moreover, ACDs can inhibit the activity of cell wall-related enzymes in Gram-negative bacteria by changing the enzymatic secondary structure. This work is of great significance for the development of new antibacterial nanomaterials derived from natural biomass as well as the treatment of infections caused by Gram-negative bacteria.

In this study, the regenerated porous cellulose film (LD) was properly prepared by dissolving cellulose in a LiCl/DMAc solvent though a simple phase inversion method. LD has a porous structure, good mechanical properties and great thermal stability. In order to form a shape-stabilized reversible thermochromic phase change film (DTLD), a reversible thermochromic compound (DTBC) was added into the LD by simple vacuum impregnation. The effect of the weight ratio of 1-dodecanol/tetradecanol complex solvent (3 : 7, 2 : 8, 1.5 : 8.5 and 1 : 9) on the phase change properties was investigated. DTLD (1.5 : 8.5) showed the highest latent heat storage of 174.00 J g -1 with the suitable phase change temperature at 37.5 °C. The low thermal conductivity of DTLD (1.5 : 8.5) at 10 °C (50 °C) was 0.396 ± 0.004 W m -1 K -1 (0.408 ± 0.002 W m -1 K -1 ). The color of DTLD (1.5 : 8.5) can change reversibly between colorless and blue as temperature changes. Melting-cooling tests after 100 cycles indicated that DTLD (1.5 : 8.5) has a high latent heat storage capacity of 169.65 J g -1 . A shape-stable reversible thermochromic phase change composite assembled from a regenerated porous cellulose membrane as a support matrix is expected to be applied to the field of thermal energy storage., Competing Interests: No conflict of interest exits in the submission of this manuscript., (This journal is © The Royal Society of Chemistry.)

An iron-catalyzed one-pot three-component reaction of 1-substituted benzimidazoles with diazoacetates and electron-deficient alkynes or alkenes has been reported. Mechanistically, the reaction goes through a 1,3-dipolar cycloaddition of catalytically generated benzimidazolium N-ylides with various activated alkynes or alkenes, leading to multi-substituted and polycyclic fused pyrrole derivatives, respectively.

We report the development of a new type of organic semiconductor gas sensor based on a porphyrin-based hydrogen-bonded organic framework (HOF). Owing to the orderly porous structures, the decoration with rich amino sites and the n-type semiconductor nature, this HOF-based sensor exhibits selective NO 2 sensing performance with ultra-fast response/recovery rates (17.6 s/15.4 s over 100 ppb) and a limit of detection lower than 40 ppb, together with high sensitivity, good reproducibility, and long-term stability at room temperature. This study demonstrates that HOF-based materials have potential application prospects in gas sensing, thereby offering a new way of thinking for the design and development of sensors.

A rhodium-catalyzed three-component reaction of diazo compounds, anilines and C,N-cyclic azomethine imines via trapping of transient ammonium ylides was developed. This reaction provided a simple and convenient approach for the synthesis of pharmaceutically intriguing tetrahydroisoquinoline derivatives in moderate to good yields (36-85%) with good diastereoselectivities (up to 95 : 5 dr) under mild reaction conditions.

It is important to determine the time-dependent evolution of the excited monolayer WS 2 , which will provide a basis for the reasonable design of optoelectronic devices based on two-dimensional transition metal dichalcogenides. Here, we made a simple and large-area photodetector based on the monolayer WS 2 , with high light sensitivity and fast response, benefiting from the special dynamics of carrier involving the exciton, trion, and charge. Moreover, we tested the relaxation behavior of the excited monolayer WS 2 by employing transient absorption (TA). It was found that the multi-body interaction among exciton would occur after the density of pump photon increases to 3.45 × 10 14 photons per cm 2 . The exciton dissociation accompanying the generation of trion would appear in the photo-induced relaxation process, which would be a benefit for the operation of this photodetector. Increasing the energy of the exciton is good for the generation of carrier by comparing the relaxation behavior of WS 2 excited to A and B exciton states. However, the bound exciton relaxation, originating from the capture process of the defect state, would exist and play an unfavorable role during the functioning of devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Graphitic carbon nitride (g-C 3 N 4 ) has attracted wide attention due to its potential in solving energy and environmental issues. However, rapid charge recombination and a narrow visible light absorption region limit its performance. In our study, Mg-doped g-C 3 N 4 was synthesized through a facile one-pot strategy for CO 2 reduction. After Mg doping, the light utilization efficiency and photo-induced electron-hole pair separation efficiency of the catalysts were improved, which could be due to the narrower band gap and introduced midgap states. The highest amounts of CO and CH 4 were obtained on Mg-CN-4% under ultraviolet light illumination, which were about 5.1 and 3.8 times that of pristine g-C 3 N 4 , respectively; the yield of CO and CH 4 reached 12.97 and 7.62 μmol g -1 under visible light irradiation. Our work may provide new insight for designing advanced photocatalysts in energy conversion applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We demonstrate nonlinear optical modulation by combining mesoporous carbon nanospheres (MCNs) and D-shaped fibers (DFs). The MCNs are prepared by the silica-assisted strategy and the DFs are fabricated through a precision wheel polishing method. When the MCNs are deposited onto the DF as the saturable absorbers (SAs), the SAs possess broadband linear absorption and nonlinear saturable absorption properties. As the DF-MCNs SA is integrated into the laser cavities, ultrafast lasers at 1.56 and 2 μm were realized with minimal pulse duration down to a few hundreds of femtoseconds. Compared with the film and microfiber-based MCNs-SAs, the DF-MCNs SAs exhibit greater robustness and stronger evanescent field, and are more effective at generating femtosecond pulses. Our results verify that DF-MCNs as a kind of cost-effective and easily-prepared SA would be of great importance for stable and high-power femtosecond fiber lasers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Gene therapy as a strategy for disease treatment requires safe and efficient gene delivery systems that encapsulate nucleic acids and deliver them to effective sites in the cell. Due to the insecurity of viral vectors, non-viral vectors have gained great attention recently. Additional advantages of non-viral vectors include their safety, flexibility in packaging nucleic acids, and ease of production. To construct an ideal gene carrier, peptides can be incorporated into non-viral gene delivery systems as functional motifs to overcome the current barriers in gene delivery. In this review, we summarize recent developments in peptide-based gene delivery vector research.

Exploring efficient non-noble ORR catalysts as alternatives to Pt-based catalysts are highly demanded for their possible application in fuel cells and rechargeable metal-air batteries. Herein, we demonstrate a rational design and synthesis of a N, P-doped carbon with encapsulated Co nanoparticles as efficient electrocatalysts for ORR. The catalyst is derived from a mixture of Co-MOF and triphenylphosphine with a mass ratio of 3 : 1 by pyrolysis in N2 atmosphere at 700 °C. The catalyst exhibited a superior ORR catalytic performance among its counterparts in 0.1 M KOH with onset and half-wave potentials of 0.88 V and 0.80 V, a much larger limiting current density of -5.93 mA cm-2 that surpassed commercial 20% Pt/C, in addition to its durability and resistance to methanol. This enhanced ORR activity of the catalyst can be attributed to the synergistic effect between Co NPs and N, P atoms, the relatively large contact surface, more exposed active sites and good electrical conductivity. This study would provide some new ideas for the design and construction of promising carbon-based non-precious metal electrocatalysts for future practical fuel cell applications.

A highly diastereoselective approach for the rapid construction of an isochroman skeleton was achieved by the copper(ii)-catalyzed transformation of alcohol-tethered enones and diazo compounds. This transformation was proposed to proceed through the intramolecular Michael-type trapping of an in situ generated oxonium ylide intermediate. The copper(ii) catalyst may play a dual role in catalyzing diazo decomposition as well as activating the enone unit. With this method, a series of 3,4-substituted isochromans were obtained with excellent diastereoselectivities under very mild reaction conditions.

Multifunctional carbon dots (CDs) with lifetime thermal sensing, nucleolus imaging, and antialgal activity properties were synthesized directly from ascorbic acid aqueous solution by a one-step electrochemical method at room temperature. The as-prepared CDs are responsive to temperature and exhibit an accurate linear response of fluorescence intensity vs. temperature (20-100 °C). These CDs can enter a cell and nucleolus, adsorb on the nucleic acids (DNA and RNA) and the fluorescence intensity of CDs is increased by the adsorption of nucleic acids. In addition, the CDs can inhibit the activity of RuBisCO in Anabaena sp., leading to reducing the growth of Anabaena sp. All these properties make the CDs serve as effective fluorescence-based nanothermometers, nucleolus probes, and antialgal agents.

We designed a series of peptide vectors that contain functional fragments with the goal of enhancing cellular internalization and gene transfection efficiency. The functional fragments included a cell-penetrating peptide (R 9 ), a cationic amphiphilic α-helical peptide [(LLKK) 3 -H 6 or (LLHH) 3 ], a stearyl moiety, and cysteine residues. Vectors were also synthesized with D-type amino acids to improve their proteolytic stability. The conformations, particle sizes, and zeta potentials for complexes of these peptides with pGL3 plasmid DNA were characterized by circular dichroism and dynamic light scattering. In addition, cellular uptake of the peptide/DNA complexes and gene transfection efficiency were investigated with fluorescence-activated cell sorting and confocal laser-scanning microscopy. Greater transfection efficiency was achieved with the vectors containing the R 9 segment, and the efficiency was greater than Lipo2000. In addition, the D-type C 18 -c(llkk) 3 ch 6 -r 9 had about 7 times and 5.5 times the transfection efficiency of Lipo2000 in 293T cells and NIH-3T3 cells at the N/P ratio of 6, respectively. Overall, the multifunctional peptide gene vectors containing the R 9 segment exhibited enhanced cellular internalization, a high gene transfection efficiency, and low cytotoxicity., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)