Search

The efficiency of photocatalysts depends largely on the accessibility of reaction species to the active centre, the electron transfer and geometric matching between the active surface of the catalyst and reaction species. In this work, we successfully synthesized and designed one two-dimensional Mn(II) MOF with [Mn 2 (H 2 L1)(H 2 O) 2 (DMF) 2 ] n ·(CH 3 CH 2 OH) n (HSTC 3) by using MnCl 2 ·4H 2 O and 5,5'-(anthracene-9,10-diyl)diisophthalic acid (H 4 L1), in which the adjacent layers are stacked with weak interactions, and the huge gap leads to the interpenetration between layers to form a 2D + 2D → 3D interpenetration frame. Based on the particularity of the structure of HSTC 3, ultrasonic wall breaking methods were tried to successfully peel HSTC 3 into nanosheets (HSTC 3-NS), thus achieving a significant improvement in a series of optoelectronic properties due to exposure to more active centres for HSTC 3-NS. These results significantly enhance the photocatalytic selective oxidation of thioether. This study provides a new insight into the post-synthesis modification of MOF photocatalyst and their application in photocatalytic organic synthesis.

DNA conformations, which encompass the three-dimensional structures of the DNA strand, play a crucial role in genome regulation. During DNA translocation in a nanopore, various conformations occur due to interactions among force fields, the fluidic environment, and polymer features. The most common conformation is folding, where DNA moves through the nanopore in a two-strand or multi-strand manner, influencing the current signature. Factors such as hydrodynamic drag, ionic environments, and DNA length significantly affect these conformations. Notably, conical nanopores, with their asymmetrical geometry, impose unique constraints on DNA translocation. Our findings reveal that during forward translocation, from the narrow ( cis ) end to the wide ( trans ) end, DNA experiences less resistance, resulting in shorter translocation times and higher blockade currents. Conversely, backward translocation, from the wide ( trans ) end to the narrow ( cis ) end, leads to longer translocation times and more complex conformations due to increased hydrodynamic drag and geometric constraints. This study employs molecular ping-pong methods to confine DNA, further highlighting the intricate dynamics of DNA folding within nanopores. These insights enhance the understanding of DNA behavior in confined environments, contributing to advancements in nanopore-based sensing and sequencing technologies, with implications for genome regulation and biomedical applications.

Li-rich layered oxides are promising candidates for high-capacity Li-ion battery cathode materials. In this study, we employ first-principles calculations to investigate the effect of F doping on Li-rich Li 2 MnO 3 layered cathode materials. Our findings reveal that both Li 2 MnO 3 and Li 2 MnO 2.75 F 0.25 exhibit significant volume changes (greater than 10%) during deep delithiation, which could hinder the cycling of more Li ions from these two materials. For Li 2 MnO 3 , it is observed that oxygen ions lose electrons to compensate for charge during the delithiation process, leading to a relatively high voltage plateau. After F doping, oxidation occurs in both the cationic (Mn) and anionic (O) components, resulting in a lower voltage plateau at the beginning of the charge, which can be attributed to the oxidation of Mn 3+ to Mn 4+ . Additionally, F doping can somewhat suppress the release of oxygen in Li 2 MnO 3 , improving the stability of anionic oxidation. However, the increase of the activation barriers for Li diffusion can be observed after F doping, due to stronger electrostatic interactions between F - and Li + , which adversely affects the cycling kinetics of Li 2 MnO 2.75 F 0.25 . This study enhances our understanding of the impact of F doping in Li 2 MnO 3 based on theoretical calculations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, we explore the mass transfer and separation mechanism of Li + and Mg 2+ confined within the flexible nanoporous zeolite imidazolate framework ZIF-8 under the influence of an electric field, employing molecular dynamics simulation. Our results highlight that the electric field accelerates the dehydration process of ions and underscore the critical importance of ZIF-8 framework flexibility in determining the separation selectivity of the ZIF-8 membrane. The electric field is shown to diminish ion hydration in the confined space of ZIF-8, notably disrupting the orientation of water molecules in the first hydration shells of ions, leading to an asymmetrical ionic hydration structure characterized by the uniform alignment of water dipoles. Furthermore, despite the geometrical constraints imposed by the ZIF-8 framework, the electric field significantly enhances ionic mobility. Notably, the less stable hydration shell of Li + facilitates its rapid, dehydration-induced transit through ZIF-8 nanopores, unlike Mg 2+ , whose stable hydration shell impedes dehydration. Further investigation into the structural characteristics of the six-ring windows traversed by Li + and Mg 2+ ions reveals distinct mechanisms of passage: for Mg 2+ ions, significant window expansion is necessary, while for Li + ions, the mechanism involves both window expansion and partial dehydration. These findings reveal the profound impact of the electric field and framework flexibility on the separation of Li + and Mg 2+ , offering critical insights for the potential application of flexible nanoporous materials in the selective extraction of Li + from salt-lake brine.

Experimental studies have shown that vitamin C has anti-cancer effects, but previous meta-analyses have indicated that the role of vitamin C in digestive system cancers (DSCs) is controversial. In this study, a systematic review and meta-analysis of the relationship between dietary intake/plasma concentration of vitamin C and the risk of DSC was conducted, evaluating 32 prospective studies with 1 664 498 participants. Dose-response and subgroup analyses were also performed. Systematic literature searches were performed in PubMed, EMBASE and Web of Science databases until 9 th September 2023. Vitamin C intake significantly reduced DSCs risk (RR = 0.88, 95% confidence interval (CI) 0.83 to 0.93). The subgroup analyses showed the risks of oral, pharyngeal, and esophageal (OPE) cancers (0.81, 0.72 to 0.93), gastric cancer (0.81, 0.68 to 0.95), and colorectal cancer (0.89, 0.82 to 0.98) were negatively correlated with vitamin C intake, and the effect of vitamin C was different between colon cancer (0.87, 0.77 to 0.97) and rectal cancer (1.00, 0.84 to 1.19). However, plasma vitamin C concentration was only inversely associated with gastric cancer risk (0.74, 0.59 to 0.92). Dose-response analysis revealed that 250 and 65 mg day -1 vitamin C intakes had the strongest protective effect against OPE and gastric cancers respectively. These estimates suggest that vitamin C intake could significantly reduce gastrointestinal cancer incidence, including OPE, gastric, and colon cancers. Plasma vitamin C has a significant reduction effect on the incidence of gastric cancer only, but additional large-scale clinical studies are needed to determine its impact on the incidence of DSCs.

A through-space charge transfer pyrene-based fluorophore has been developed for organic light-emitting devices (OLEDs). This material exhibits deep-blue fluorescence, bipolar characteristics, and anti-quenching behavior in the solid state. It proves to be an effective emitter for both doped and nondoped deep-blue OLEDs.

Room-temperature sodium-sulfur (RT Na-S) batteries have the drawbacks of the poor shuttle effect of soluble sodium polysulfides (NaPSs) as well as slow sulfur redox kinetics, which result in poor cycling stability and low capacity, seriously affecting their extensive application. Herein, defect engineering is applied to construct rich oxygen vacancies at the interface of a TiO 2 anatase/rutile homojunction (O V -TRA) to enhance sulfur affinity and redox reaction kinetics. Combining structural characterizations with electrochemical analysis reveals that O V -TRA well alleviates the shuttle effect of NaPSs and precipitates the deposition and diffusion kinetics of Na 2 S. Consequently, S/O V -TRA provides excellent electrochemical performance with a reversible capacity of 870 mA h g -1 at 0.1 C after 100 cycles and a long-term cycling capability of 759 mA h g -1 at 1 C after 1000 cycles. This work provides an effective interfacial defect engineering strategy to promote the application of metal oxides in RT Na-S batteries.

Although lithium-sulfur (Li-S) batteries have attracted strong consideration regarding their fundamental mechanism and energy applications, the inferior cycling performance and low reaction rate caused by the "shuttling effect" and the sluggish reaction kinetics of lithium polysulfides (LiPSs) impede their practical application. In this work, graphitic C 3 N 4 (g-C 3 N 4 ) assembled with highly-dispersed nitrogen-containing carbon quantum dots (CQDs) is designed as a cooperative catalyst to accelerate the reaction kinetics of LiPS conversion, the precipitation of Li 2 S during discharging, and insoluble Li 2 S decomposition during the charging process. Meanwhile, the introduction of CQDs improves the conductivity of the g-C 3 N 4 substrate, showing great significance for the construction of high-performance electrocatalysts. As a result, the as-obtained composite shows efficient adsorption and electrochemical conversion of LiPSs, and the Li-S batteries assembled with CQDs/g-C 3 N 4 exhibit an initial specific capacity of 1300.0 mA h g -1 at the current density of 0.1C and retain 582.3 mA h g -1 after 200 cycles. The electrode with the modified composite displays a greater capacity contribution of Li 2 S precipitation (175.7 mA h g -1 ), indicating an enhanced catalytic activity of g-C 3 N 4 decorated by CQDs. The rational design of CQDs/g-C 3 N 4 as a sulfur host could be an effective strategy for developing high performance Li-S batteries.

There is a high demand from aging people for facial fillers with desirable biocompatibility and lasting filling effects to overcome facial depression. Novel injectable regenerated silk fibroin (RSF) microparticles were facilely printed from a glycidyl methacrylate-modified silk fibroin hydrogel to address this issue. The β-sheet content and mechanical properties of the RSF hydrogel can be simply modulated by the number of freeze-thawing cycles, and the swelling rate of the RSF hydrogel in saline was negligible. The printed RSF microparticles were uniform, and their diameter was about 300-500 μm, which could be adjusted by the pore sizes of the printed screens. After the injection with a 26-gauge needle, the size distribution of RSF microparticles had no noticeable variation, suggesting that the microparticles could bear the shear strain without breaking during the injection. The in vitro experiments demonstrated that RSF not only had desirable biocompatibility but also facilitated fibroblast migration. The subcutaneous injection experiments demonstrated that the RSF microparticles formed a lasting spot in the injected site. The tissue sections revealed that the RSF microparticles were still distinct on week 8, and blood vessels formed around the microparticles. These promising data demonstrate that the printed RSF microparticles have great potential for facial rejuvenation.

Developing a comprehensive strategy for imaging various biomarkers ( i.e. , microRNAs and proteases) in vivo is an exceptionally formidable task. Herein, we have designed a deoxyribonucleic acid-gold nanocluster (DNA-AuNC) nanomachine for detecting tumor-related TK1 mRNA and cathepsin B in living cells and in vivo . The DNA-AuNC nanomachine is constructed using AuNCs and DNA modules that incorporate a three component DNA hybrid (TD) and a single-stranded fuel DNA (FD). Upon being internalized into tumor cells, the TK1 mRNA initiates the DNA-AuNC nanomachine through DNA strand displacement cascades, leading to the amplified self-assembly and the aggregation-enhanced emission of AuNCs for in situ imaging. Furthermore, with the aid of a protease nanomediator consisting of a mediator DNA/peptide complex and AuNCs (DpAuNCs), the DNA-AuNC nanomachine can be triggered by the protease-activated disassembly of the DNA/peptide complex on the nanomediator, resulting in the aggregation of AuNCs for in vivo protease amplified detection. It is worth noting that our study demonstrates the impressive tumor permeability and accumulation capabilities of the DNA-AuNC nanomachines via in situ amplified self-assembly, thereby facilitating prolonged imaging of TK1 mRNA and cathepsin B both in vitro and in vivo . This strategy presents a versatile and biomarker-specific paradigm for disease diagnosis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Boron-carbon compounds have been shown to have feasible superconductivity. In our earlier paper [Zheng et al. , Phys. Rev. B , 2023, 107 , 014508], we identified a new conventional superconductor of LiB 3 C at 100 GPa. Here, we aim to extend the investigation of possible superconductivity in this structural framework by replacing Li atoms with 27 different cations from periods 3, 4, and 5 under pressures ranging from 0 to 100 GPa. Using the high-throughput screening method of zone-center electron-phonon interaction, we found that ternary compounds like CaB 3 C, SrB 3 C, TiB 3 C, and VB 3 C are promising candidates for superconductivity. The consecutive calculations using the full Brillouin zone confirm that they have a T c of <31 K at moderate pressures. Our study demonstrates that fast screening of superconductivity by calculating zone-center electron-phonon coupling strength is an effective strategy for high-throughput identification of new superconductors.

Polar metals have generated significant interest since the ferroelectric-like structural transition in metallic LiOsO 3 was discovered. Herein, we report on a strain-modulated polar metal in the ferroelectric/metal superlattice of 1 : 1 KNbO 3 /CaNbO 3 . Using first-principles calculations, we have investigated the structural distortions, including polar distortions and octahedral rotations, and layer-by-layer electronic structures in the KNbO 3 /CaNbO 3 superlattice under different epitaxial strains. Along the stacking direction, the superlattice has almost parallel polar displacements under compressive strain, whereas both in-plane and out-of-plane antiferroelectric-like polar displacements are robust under intermediate strain, which is connected to the octahedral tilting pattern and interlayer electron transfer. In addition, the in-plane polar distortions are enhanced by tensile strains and have a sudden increase at 4% tensile strain. The metallicity is mainly contributed by d electrons from Nb atoms. And orbital-resolved electron distributions in each layer show that d-orbital splitting is related not only to the epitaxial strain but also to the direction of polar displacements. Our results suggest an efficient way to tune polar distortions as well as local metallicity via epitaxial strains in the superlattice.

Two kinds of magnetic-responsive solid acid catalysts were designed and prepared via an in situ polymerization of poly(ionic liquid)s (PILs) on the surface of Fe 3 O 4 @SiO 2 NPs for the catalyzed esterification of palmitic acid and methanol. They were characterized using XRD, TGA, VSM, NMR spectroscopy, FTIR spectroscopy, XPS, SEM, and GC techniques. The results confirmed the preparation of solid acid catalysts. Meanwhile, they possessed excellent catalytic activity and recyclability. The effect of the reaction conditions on the esterification was investigated through single-factor analyses, and the proposed catalytic mechanism of the prepared solid acid catalysts in the esterification are also discussed. Under the optimal reaction conditions (10 wt% catalyst, 6 h, 70 °C, and molar ratio (MR) of methanol to palmitic acid of 12 : 1), the conversion rate of palmitic acid could reach 94% and 79% with Fe 3 O 4 @SiO 2 -poly(1-vinyl-3-ethylimidazolium phosphotungstate) (Fe 3 O 4 @SiO 2 -P([VLIM]PW)) and Fe 3 O 4 @SiO 2 -poly(1-vinylimidazole-3-propyl sulfonate) (Fe 3 O 4 @SiO 2 -P([VLIM]SO 3 )) NPs serving as catalysts, respectively. Furthermore, the Fe 3 O 4 @SiO 2 -P([VLIM]PW) NPs could still maintain a high catalytic activity even after being reused 5 times without significant deactivation., Competing Interests: The authors state that there are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A double-chain structure was fabricated on Au (111) with a bromine-functionalized phenanthroline precursor. We reveal the competition between the on-surface metal-ligand coordination and C-C coupling of the precursor by scanning tunneling microscopy (STM) imaging and density functional theory (DFT) calculations at the molecular level. Our work provides an additional strategy for controlling the on-surface polymerization, which is of great relevance to the construction of novel nanostructures.

As a chronic inflammatory disease, rheumatoid arthritis (RA) can cause progressive damage to joints and various organs. Hydrogen peroxide plays a significant role in the pathogenesis and progression of RA and thus serves as a biomarker for diagnosing this disease. Although fluorescent probes have emerged as promising tools for detecting H 2 O 2 , most available ones suffer from the aggregation-caused quenching (ACQ) effect, short-wavelength emission, low sensitivity, and poor water solubility. Herein, a new type of "turn-on" AIE probe based on excited state intramolecular proton transfer (ESIPT) was developed, with phenylboronic acid pinacol ester-appended quinolinium as the H 2 O 2 recognition site, which is in the quenched state due to the twisted intramolecular charge transfer (TICT) effect. The probe HTQ-R exhibits good water solubility, high sensitivity, a low detection limit (210 nM), rapid response ability, and good biocompatibility towards hydrogen peroxide, and has shown the ability to accurately target mitochondria. Furthermore, HTQ-R was successfully used to detect exogenous and endogenous hydrogen peroxide in living cells, which enabled real-time monitoring of H 2 O 2 in RA mice, demonstrating its potential significance in the diagnosis and treatment of RA.

Recently, nanomedicine design has shifted from simple nanocarriers to nanodrugs with intrinsic antineoplastic activities for therapeutic performance optimization. In this regard, degradable nanomedicines containing functional inorganic ions have blazed a highly efficient and relatively safe ion interference paradigm for cancer theranostics. Herein, given the potential superiorities of infinite coordination polymers (ICPs) in degradation peculiarity and functional integration, a state-of-the-art dual-ICP-engineered nanomedicine is elaborately fabricated via integrating ferrocene (Fc) ICPs and calcium-tannic acid (Ca-TA) ICPs. Thereinto, Fc ICPs, and Ca-TA ICPs respectively serve as suppliers of ferrous iron ions (Fe 2+ ) and calcium ions (Ca 2+ ). After the acid-responsive degradation of ICPs, released TA from Ca-TA ICPs facilitated the conversion of released ferric iron (Fe 3+ ) from Fc ICPs into highly active Fe 2+ . Owing to the dual-path oxidative stress and neighboring effect mediated by Fe 2+ and Ca 2+ , such a dual-ICP-engineered nanomedicine effectively induces dual-ion interference against triple-negative breast cancer (TNBC). Therefore, this work provides a novel antineoplastic attempt to establish ICP-engineered nanomedicines and implement ion interference-mediated synergistic therapy.

In the presence of alcohol, cocaine metabolism produces a number of metabolites, including three toxic ones (cocaethylene, norcocaine, and norcocaethylene) which are all more toxic than cocaine itself, with the toxicity in the order of cocaine < cocaethylene < norcocaine < norcocaethylene. In this study, we performed kinetic analysis on our previously reported cocaine hydrolase (E30-6) for its catalytic activities accelerating the hydrolysis of the three toxic metabolites in comparison with cocaine. Based on the obtained kinetic data, the in vitro catalytic efficiencies of the enzyme against these substrates are in the order of cocaine > cocaethylene > norcocaine > norcocaethylene. It has been demonstrated that E30-6 can efficiently accelerate the hydrolysis of not only cocaine itself, but also all three toxic metabolites in vitro and in vivo . E30-6 is the most efficient enzyme for each of these toxic substrates (cocaine, cocaethylene, norcocaine, and norcocaethylene) among all the reported enzymes as far as we know at this point. These findings suggest that E30-6 is capable of efficiently treating cocaine toxicity even when alcohol and cocaine are used concurrently.

Layered graphene and molybdenum disulfide have outstanding sodium ion storage properties that make them suitable for sodium-ion batteries (SIBs). However, the easy and large-scale preparation of graphene and molybdenum disulfide composites with structural stability and excellent performance face enormous challenges. In this study, a self-supporting network-structured MoS 2 /heteroatom-doped graphene (MoS 2 /NSGs-G) composite is prepared by a simple and exercisable electrochemical exfoliation followed by a hydrothermal route. In the composite, layered MoS 2 nanosheets and heteroatom-doped graphene nanosheets are intertwined with each other into self-supporting network architecture, which could hold back the aggregation of MoS 2 and graphene effectively. Moreover, the composite possesses enlarged interlayer spacing of graphene and MoS 2 , which could contribute to an increase in the reaction sites and ion transport of the composite. Owing to these advantageous structural characteristics and the heteroatomic co-doping of nitrogen and sulfur, MoS 2 /NSGs-G demonstrates greatly reversible sodium storage capacity. The measurements revealed that the reversible cycle capacity was 443.9 mA h g -1 after 250 cycles at 0.5 A g -1 , and the rate capacity was 491.5, 490.5, 453.9, 418.1, 383.8, 333.1, and 294.4 mA h g -1 at 0.1, 0.2, 0.5, 1, 2, 5 and 10 A g -1 , respectively. Furthermore, the MoS 2 /NSGs-G sample displayed lower resistance, dominant pseudocapacitive contribution, and faster sodium ion interface kinetics characteristic. Therefore, this study provides an operable strategy to obtain high-performance anode materials, and MoS 2 /NSGs-G with favorable structure and excellent cycle stability has great application potential for SIBs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The advancement of nanopore sensing technology over the past 20 years has been impressive, particularly in the field of nucleic acid sequencing, which has already been used in commercial diagnostic tests. A traditional configuration of nanopore sensing records the current through a single nanopore using a voltage clamp, which hits a bottleneck in expanding its functions, while integrating several nanopores to build a nanopore circuit may be an effective solution. Here, we report a new strategy combining a nanopore series circuit and a current clamp to record the current signal and the voltage signal of DNA translocation through a nanopore simultaneously, which could increase the fidelity of event analysis. We observed a capacitor-like charging and discharging behavior in the voltage signals and proposed a detailed microscopic mechanism to elucidate it. Our strategy could benefit the development of nanopore technology and contribute to understanding the working principles of the units in a nanopore circuit system.

A 2D Dy(III) metal-organic layer (MOL 1) was synthesized under solvothermal conditions. Structural analysis suggests that the Dy(III) ions in each one-dimensional (1D) arrangement are evenly arranged in the form of broken lines. The 1D chains are linked to one another via ligands to form a 2D layer that generates a 2D surface with elongated apertures. The photocatalytic activity study suggests that MOL 1 exhibits good catalytic activity in flavonoids by the formation of an O 2 ˙ - radical as an intermediate. This is the first reported method of synthesizing flavonoids using chalcones.

Heteroatom-doped porous carbon materials have been widely used as anode materials for Li-ion and Na-ion batteries, however, improving the specific capacity and long-term cycling stability of ion batteries remains a major challenge. Here, we report a facile based metal-organic framework (MOFs) strategy to synthesize nitrogen-doped porous carbon nanofibers (NCNFs) with a large number of interconnected channels that can increase the contact area between the material and the electrolyte, shorten the diffusion distance between Li + /Na + and the electrolyte, and relieve the volume expansion of the electrode material during cycling; the doping of nitrogen atoms can improve the conductivity and increase the active sites of the carbon material, can also affect the microstructure and electron distribution of the electrode material, thereby improving the electrochemical performance of the material. As expected, the obtained NCNFs-800 exhibited excellent electrochemical performance with high reversible capacity (for Li + battery anodes: 1237 mA h g -1 at 100 mA g -1 after 200 cycles, for Na + battery anodes: 323 mA h g -1 at 100 mA g -1 after 150 cycles) and long-term cycling stability (for Li + battery anodes: 635 mA h g -1 at 2 A g -1 after 5000 cycles, for Na + battery anodes: 194 mA h g -1 at 2 A g -1 after 5000 cycles)., Competing Interests: There are no conflicts for this work to declare., (This journal is © The Royal Society of Chemistry.)

A heptazine-based, partially cross-linked carbon nitride (PC-CN) was successfully prepared via a solid-chloride-salt-assisted polycondensation method. The cross-linking favors the charge transport between different chains, thus dramatically boosting the photocatalytic hydrogen evolution activity of PC-CN, up to 29.3 times that of traditional 1D-CN.

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.

The identification of drugs or biomolecules for public health monitoring requires facile analytical technologies with excellent sensitivity, portability and reliability. In the past decades, different sensing materials have inspired the development of various bioanalytical strategies. However, sensing platforms based on powder materials are not suitable for medical diagnosis, which limits further exploration and application of biosensors. Herein, a point-of-care testing (POCT) membrane was designed from an energy competition mechanism and achieved the detection of the nonsteroidal antiphlogistic diclofenac, and exhibited remarkable testing efficacy at the ppb level. The mixed matrix membrane (MMM) sensor consists of electrospun polyacrylonitrile nanofibers and luminescent Tb-MOFs and possess the advantages of high stability, outstanding anti-interference ability, efficient detection (LOD = 98.5 ppb) and easy visual recognition. Furthermore, this MMM sensor exhibits excellent recyclability in serum, which is beneficial for developing a portable and convenient device to distinguish diclofenac in practical sensing applications. Meanwhile, the feasibility and mechanism of this recyclable sensor were verified by theory and experiments, indicating that it is a promising device for diclofenac detection in biological environments to evaluate the toxic effect caused by the accumulation of nonsteroidal drugs.

By taking advantage of the slight difference in the acidity of D 2 O and H 2 O, we report a novel D 2 O optical sensor, namely Cy, with integrated great water-solubility, absorption/fluorescence dual-channel ratiometric response and even RGB visual sensing application. This work puts forward a facile method for distinguishing D 2 O from H 2 O with high sensitivity and high accuracy.

Enhanced and balanced carrier injection is essential to achieve highly efficient green indium phosphide (InP) quantum dot light-emitting diodes (QLEDs). However, due to the poor injection of holes in green InP QLEDs, the carrier injection is usually balanced by suppressing the strong electron injection, which decreases the radiation recombination rate dramatically. Here, an electric dipole layer is introduced to enhance the hole injection in the green InP QLED with a high mobility electron transport layer (ETL). The ultra-thin MoO 3 electric dipole layer is demonstrated to form a positive built-in electric field at the interface of the hole injection layer (HIL) and hole transport layer (HTL) due to its deep conduction band level. Simulation and experimental results support that strong electric fields are produced for efficient hole hopping, and the carrier recombination rate is substantially increased. Consequently, the green InP QLEDs based on enhanced electron and hole injection have achieved a high luminance of 52 730 cd m -2 and 1.7 times external quantum efficiency (EQE) enhancement from 4.25% to 7.39%. This work has provided an effective approach to enhance carrier injection in green InP QLEDs and indicates the feasibility to realize highly efficient green InP QLEDs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

On-surface synthesis has been a subject of intensive research during the last decade. Various chemical reactions have been developed on surfaces to prepare compounds and carbon nanostructures, most of which are centered on the carbon-carbon bond formation. Despite the vast progress so far, the diversity of functional groups in organic chemistry has been far less explored in on-surface synthesis. Herein, we study the surface-assisted synthesis of ethers through the homocoupling of hydroxymethyl substituents on Ag(111). By using two hydroxymethyl substituent functionalized molecular precursors with different symmetries, we have achieved the formation of ether chains and rings. High-resolution scanning tunneling microscopy complemented with density functional theory calculations are used to support our findings and offer mechanistic insights into the reaction. This work expands the toolbox of on-surface reactions for the bottom-up fabrication of more sophisticated functional nanostructures.

It is a challenging task to explore highly active and stable noble-metal-free bifunctional electrocatalysts for water splitting, both in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, a new dual-confinement strategy for the fabrication of cobalt-base phosphide in the carbon nanofibers (CNFs) was proposed via electrospinning, followed by the corresponding pyrolysis. The ultrafine phosphides derived from the pore confinement of ZIF and space confinement of the polymer revealed abundant active sites and P defects. More importantly, by introducing a second metal element Ni or Cu, the electronic structure and synergistic effect were further enhanced, and the obtained bimetallic CoNiP x -CNF electrocatalyst exhibited the remarkable performance for HER and OER, featuring the low η 10 values of 154 and 269 mV in 1.0 M KOH electrolyte, respectively. CoNiP x -CNFs as a catalyst for both anode and cathode showed a current density of 10 mA cm -2 at a voltage of 1.56 V, exceeding better stability, which is superior to most non-noble metal electrocatalysts reported in a previous research. The dual-confinement strategy is believed to provide an effective and simple approach for the synthesis of high-performance and cost-efficient bifunctional electrocatalysts for overall water splitting.

Perovskite quantum dots (PQDs) are promising interface modification materials for perovskite solar cells (PSCs). However, due to the limitation of the preparation method, it is hard to use PQDs as substrates for the growth of perovskite films by the common solution process. In this work, by introducing the rare earth element Ce into PQDs with the vacuum freezing and drying technology, we have successfully improved the solvent stability of PQDs. Moreover, we propose a technology, PQD dynamically mediated growth of perovskite film (PDMG), to prepare high-quality perovskite films, which can avoid the formation of PQD charge-blocking layers. Thanks to the improvement of perovskite crystallinity and the charge transport ability, the PCE is improved from 10.44% to 12.14% for CsPbI 2 Br PSCs and from 14.43% to 16.38% for CsPbI 3 PSCs. Our work opens an avenue for using PQDs as substrates in the fabrication of highly efficient PSCs.

Photothermal therapy (PTT), as a promising antineoplastic therapeutic strategy, has been harnessed to restrain tumor growth through near-infrared (NIR) irradiation mediated thermal ablation. Nevertheless, its biological applications are hampered by thermal diffusion and up-regulated heat shock proteins (HSPs). Herein, a versatile nanotheranostic agent is developed via integrating Zn 0.2 Fe 2.8 O 4 nanoparticles (NPs), polydopamine (PDA), and MnO 2 NPs for T 1/ T 2 dual-modal magnetic resonance (MR) imaging-guided and self-augmented PTT. The as-designed Zn 0.2 Fe 2.8 O 4 @PDA@MnO 2 NPs adequately serve as a PTT agent to realize effective photothermal conversion and obtain local hyperthermia. Additionally, the Zn 0.2 Fe 2.8 O 4 @PDA@MnO 2 NPs can significantly consume overexpressed glutathione (GSH) and generate Mn 2+ in the tumor microenvironment (TME), thus destroying redox homeostasis and catalytically generating hydroxyl radicals (˙OH) for HSP suppression and PTT enhancement. Meanwhile, Mn 2+ and Zn 0.2 Fe 2.8 O 4 NPs significantly strengthen T1- and T2-weighted MR contrast for tumor imaging and PTT guidance. Hence, this study offers proof of concept for self-augmented PTT and T 1/ T 2 dual-modal MR imaging for tumor elimination.

In recent years, Au and Ag nanomaterials have been widely used in the determination of glucose owing to their specific properties such as large specific surface area, high extinction coefficient, strong localized surface plasmon resonance effect and enzyme-mimicking activity. Compared with other methods, colorimetric determination of glucose with Au or Ag nanomaterials features the advantages of simple operation, low cost and easy observation. In this review, several typical synthesis methods of Au and Ag nanomaterials are introduced. Strategies for the colorimetric determination of glucose by Au or Ag nanomaterials are elaborated. The challenges and prospects of the application of Au or Ag nanomaterials for colorimetric detection of glucose are also discussed.

Physical technology is the main method to separate metal and non-metallic fractions from printed circuit boards (PCBs). The non-metallic fractions from magnetic and electrostatic separation have different ingredients, which enables them to be prepared into pyrolytic carbon with different properties. To discover the influence of separation technologies for PCBs on the preparation, characterization and application of pyrolytic carbon, two kinds of nonmetal fraction from magnetic and electrostatic separation were chosen as the precursors of pyrolytic carbon. The thermogravimetric analysis of non-magnetic fraction and non-conductive fraction at different heating rates was discussed in the paper. The optimal heating rate of 10 °C min -1 was applied in preparing pyrolytic carbons. Pyrolytic carbons prepared from the non-magnetic fraction and non-conductive fraction had visible differences in their morphological and pore structures. Pyrolytic carbons of the non-magnetic fraction exhibited higher BET surface area (313 m 2 g -1 ) and higher adsorption capacities for ciprofloxacin (142.82 mg g -1 ) than those of pyrolytic carbon of the non-conductive fraction ( S BET : 235 m 2 g -1 , q m : 78.17 mg g -1 ). Equilibrium data fit better to the Freundlich model than the Langmuir model. According to the calculated thermodynamic parameters, CIP adsorption processes by the two pyrolytic carbons were spontaneous and endothermic. Although the metal recovery from PCBs through electrostatic separation is higher, pyrolytic carbon prepared from the non-magnetic fraction shows better pore characteristics and adsorption properties. This paper might be the first report of the effect of separation technology for PCBs on the preparation of pyrolytic carbons. This paper contributed to the reutilization of non-metallic fractions of PCBs and the development of a cyclic economy., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this paper, we designed a three-band narrowband perfect absorber based on bulk Dirac semi-metallic (BDS) metamaterials. The absorber consists of a hollow Dirac semi-metallic layer above, a gold layer below and a photonic crystal slab (PCS) in the middle. The study found that the terahertz wave absorber achieved three perfect absorption rates of more than 95% in the range of 1 to 2.4 THz. The minimum bandwidth (FWHM) is 0.02 THz, and the maximum quality factor (Q) is 106. A reasonable explanation of high absorption can be obtained by impedance matching, electric dipole and other principles. The absorption spectra of the two polarizations show different responses at different incident angles. In addition, we also obtained the influence of the structural parameters of the upper layer of the metamaterial on the absorption performance. We defined the refractive index sensitivity (S) with a maximum sensitivity of 0.1525 THz RIU -1 and a highest quality factor (FOM) of 4.26 in the refractive index range of 1 to 1.8. The maximum adjustable range is 0.06 THz in the Fermi energy range of 60 to 140 meV. Because of its excellent characteristics, our absorber will have good development prospects in the fields of optical switching, biochemical imaging, and space detection.

Malvidin (MV) and its derivatives, such as malvidin-3-O-guaiacol (Mv3C) and malvidin-3-O-6-(acrylic acid-(2-hydroxy,4-carboxy-cyclohexanol)ester)-guaiacol (Mv3ACEC), are natural compounds with antioxidant properties. However, the basic mechanisms underlying their functional activities are unclear. In this study, we show that MV, Mv3C, and Mv3ACEC inhibit reactive oxygen species production and malondialdehyde content, promote glutathione peroxidase activity, and increase superoxide dismutase levels in ARPE-19 cells treated with H 2 O 2 . Western blotting and immunofluorescence analysis revealed that MV, Mv3C, and Mv3ACEC regulate mitogen-activated protein kinase signal transduction pathways related to endoplasmic reticulum stress. Interestingly, Mv3C and Mv3ACEC showed greater beneficial properties than MV. Our results show that MV and its derivatives have potential as therapeutic compounds for ocular diseases associated with oxidative stress, such as age-related macular degeneration.

Dynamically monitoring intracellular glutathione (GSH), a crucial biomarker of oxidative stress, is of significance for the diagnosis and treatment of certain diseases. Although manganese dioxide (MnO2) based GSH fluorescent sensors have exhibited high sensitivity and good selectivity owing to the specific reactivity between GSH and MnO2, near-infrared (NIR) MnO2 based nanoprobes for GSH detection are scarce. Herein, we have developed a NIR activatable fluorescence nanoprobe for the imaging and determination of intracellular GSH based on a core-shell nanoparticle, consisting of NIR emitted gold nanocluster doped silica as the fluorescent core and manganese dioxide as the GSH-responsive shell (named AuNCs@MnO2). Due to the absorption competition mechanism, the outer MnO2 shell rather than the inner AuNCs core preferentially absorbed the excitation light, thus leading to fluorescence quenching of the inner AuNCs core. Upon addition of GSH, the fluorescence of the nanoprobe restored along with the reduction of MnO2 to Mn2+ because of the absorption competition disappearance-induced emission. The activatable fluorescence linearly increased upon changing the GSH concentration in the range of 2 to 5000 μM with a detection limit of 0.67 μM. The cytotoxicity test shows that the AuNCs@MnO2 nanoprobes have a good biocompatibility. After entering the cancer cells, the intracellular GSH degraded the outermost MnO2 shell and initiated the NIR fluorescence restoration of AuNCs, which can be used to monitor the dynamic change of intracellular GSH. This strategy provides an NIR-activatable way to detect GSH levels in living cells and offers a promising platform for the diagnosis and treatment of GSH-related diseases.

Metabolic syndrome, which includes a series of metabolic disorders such as hyperglycemia, hyperlipidemia, insulin resistance and obesity, has become a catastrophic disease worldwide. Accordingly, probiotic intervention is a new strategy to alleviate metabolic syndrome, which can adjust the gut microbiota to a certain extent. The aim of the current work was to explore the alleviation of metabolic syndrome by Lactobacillus reuteri and L. rhamnosus. Two L. reuteri and two L. rhamnosus strains were administered to mice with a high-fat diet for 12 weeks. All Lactobacillus strains tested significantly slowed weight gain in the mice. Among four strains, L. reuteri FGSZY33L6 and L. rhamnosus FJSYC4-1 showed the strongest ability to relieve blood glucose disorders, blood lipid disorders, tissue damage, and particularly gut microbiota disorders. Thus, our findings indicate that these strains can regulate the gut microbiota and produce short-chain fatty acids (SCFAs), which can induce satiety hormones, inhibit food intake and increase satiety, and thus improve metabolic syndrome.

The first method for highly efficient asymmetric Michael-type Friedel-Crafts alkylation of naphthol and unsaturated pyrazolones has been accomplished under mild reaction conditions. In the presence of the chiral squaramide catalyst, a wide range of substrates are tolerated in excellent yields (up to 99%) with reasonable enantioselectivities (up to 96% ee).

Collecting water from fog flow has emerged as a promising strategy for the relief of water shortage problems. Herein, using a UV-induced (ultraviolet light induced) controllable diffusion method combined with technology of three-dimensional (3D) printing, we fabricate biomimetic materials incorporating beetle-like hydrophobic-hydrophilic character and cactus-like cone arrays with various structure parameters, and then systematically study their fog-harvesting performance. The UV-induced controllable diffusion method can break away from the photomask to regulate the hybrid wettability. Moreover, employing 3D printing technology can flexibly control the structure parameters to improve the water collection efficiency. It is found that the water collection rate (WCR) can be optimized by controlling the hybrid wettability of the sample surface and cone distance and using substrates with printed holes, which lead to a 109% increase of WCR., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report the first ESIPT-based probe ABTB, for the highly sensitive and selective imaging of formaldehyde (FA). The various theoretical calculations have been systematically performed, and clearly unravel the lighting mechanism of the fluorescent probe for FA. Additionally, the probe was successfully applied in monitoring endogenous FA in the brain of AD mice.

Carbon materials have been extensively investigated as promising negative electrode materials for lithium/sodium ion batteries. However, most common carbon materials always suffer from limitations in regards to high reversible capacity and long-term cycling stability because of their low theoretical specific capacities and sluggish kinetics. Herein, we report a facile MOF-derived strategy for the synthesis of nitrogen/oxygen co-doped porous carbon polyhedra (NOPCP) with abundant channel-connected cavities with their inner surface decorated with a large number of N and O atoms, which can provide a large number of active sites (defects and edge doping sites) for the sorption of Li + /Na + . These cavities can also be considered as "ponds" where the electrolyte is stored, which shortens the diffusion distance of ions during the discharge/charge process. When evaluated as an anode material for LIBs, NOPCP-600 delivers a high reversible capacity of 1663 mA h g -1 at 0.1 A g -1 after 120 cycles and superior cycling stability with a capacity of 667 mA h g -1 after 1000 cycles at 2 A g -1 . For SIBs, NOPCP-600 delivers a high reversible capacity of 313 mA h g -1 at 0.1 A g -1 after 100 cycles and an excellent long-term cycling stability of 228 mA h g -1 at 1 A g -1 after 2000 cycles.

Li 2 MnO 3 is a critical member of the Li-rich Mn-based layered material. To understand the process of electrochemical reaction in the monoclinic Li 2 MnO 3 , the structural evolution is investigated through the first-principles calculations based on density functional theory. During the delithiation process, a phase transformation together with a new trigonal phase at x = 0.5 (Li x MnO 3 ) has been reported, which belongs to the space group P3[combining macron]1m. Lithium ions are embedded in Li 0.5 MnO 3 until the trigonal Li 2 MnO 3 phase is formed with the P3[combining macron]1m symmetry preserved. Phonon and molecular dynamics simulations verify that this trigonal Li 2 MnO 3 is dynamically and thermodynamicaly stable. Furthermore, our calculated results reveal that it has high conductivity of 0.36 S cm -1 in the ab plane, which proves that this trigonal Li 2 MnO 3 is a promising lithium superionic conductor.

We herein developed a novel tetraarylimidazole-based AIE probe TPIG-NP to selectively image and quantitatively detect glioma. Due to the distinct negatively charged glioma cells, TPIG-NP with an opposite charge could achieve wash-free imaging of glioma cells and 3D multicellular spheroids.

Zero-dimensional (0D) quantum confinement can be achieved in perovskite materials by the confinement of electron and hole states to single PbX 6 4- perovskite octahedra. In this work, 0D perovskite (Cs 4 PbBr 6 ) micro-crystals were prepared by a simple thermally-assisted solution method and thoroughly characterized. The micro-crystals show a high level of crystallinity and a high photoluminescence quantum yield of 45%. The radiative recombination coefficient of the 0D perovskite micro-crystals, 1.5 × 10 -8 s -1 cm 3 , is two orders of magnitude higher than that of typical three-dimensional perovskite and is likely a strong contributing factor to the high emission efficiency of 0D perovskite materials. Temperature dependent luminescence measurements provide insight into the role of thermally-activated trap states. Spatially resolved measurements on single 0D perovskite micro-crystals reveal uniform photoluminescence intensity and emission decay behaviour suggesting the solution-based fabrication method yields a high-quality and homogenous single-crystal material. Such uniform emission reflects the intrinsic 0D nature of the material, which may be beneficial to device applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

β-Glucan, an economical by-product of yeast, has various health-promoting activities. However, the digestion and fermentation characteristics of β-glucan from yeast are still unknown. Thus, simulated digestion under saliva, gastric and small intestinal solutions and fermentation by gut microbiota were studied in this work. The results showed β-glucan could not be hydrolyzed in saliva, gastric and small intestinal conditions. Then, β-glucan reaches the large intestine, where it is degraded and metabolized by gut microbiota. At the same time, β-glucan could modulate the structure and composition of gut microbiota by inhibiting the proliferation of harmful gut microbiota and promoting the growth of health-promoting gut microbiota. At the phylum level, β-glucan significantly decreased the ratio of Firmicutes to Bacteroidetes. Furthermore, both β-glucan and inulin could selectively promote the growth of Bifidobacterium. Unlike inulin, β-glucan was able to better promote the growth of Bifidobacterium&#95;longum. Thus, β-glucan showed a similar probiotic activity to inulin and is expected to be a potential prebiotic for the modulation of gut microbiota.

The design and fabrication of low-cost, efficient, and robust electrocatalysts for the hydrogen evolution reaction (HER) is of great importance in accelerating the development of water electrolysis technology. Herein, NiRu alloy nanostructures embedded in a nitrogen-doped carbon matrix (NiRu@NC) have been fabricated through a facile metal-organic framework-derived (MOF-derived) strategy. Benefiting from their advantages in the unique structures and components, the resulting NiRu@NC possesses excellent activity and durability towards the HER, which exhibits low overpotentials of 85 and 53 mV at a current density of 10 mA cm-2 in acidic and alkaline electrolytes, respectively. Furthermore, NiRu2@NC-600 also exhibits excellent hydrogen oxidation reaction (HOR) activity in an alkaline electrolyte. Therefore, this work provides a facile MOF-derived strategy for the design and synthesis of low-cost and efficient electrocatalysts for the HER.

Though carbon matrices could effectively improve the electrical conductivity and accommodate the volume expansion of CuO-based anode materials for lithium ion batteries (LIBs), achieving an optimized utilization ratio of the active CuO component remains a big challenge. In this work, we developed a metal-organic framework (MOF)-derived strategy to synthesize ultrafine CuO nanoparticles embedded in a porous carbon matrix (CuO@C). Benefiting from its unique structure, the resulting CuO@C exhibits a high reversible capacity of 1024 mA h g-1 at 100 mA g-1 after 100 cycles and a long-term cycling stability with a reversible capacity of 613 mA h g-1 at 500 mA g-1 over 700 cycles. The outstanding Li-storage performances can be attributed to its porous carbon matrix and ultrafine CuO nanoparticles with more exposed active sites for electrochemical reactions.

Development of functional materials capable of exhibiting chirality tunable circularly polarized luminescence (CPL) is currently in high demand for potential technological applications. Herein we demonstrate the formation of both left- and right-handed fluorescent helical superstructures from each enantiomer of a chiral tetraphenylethylene derivative through judicious choice of the solution processing conditions. Interestingly, both the aggregation induced emission active enantiomers exhibit handedness inversion of their supramolecular helical assemblies just by varying the solution polarity without any change in their molecular chirality. The resulting helical supramolecular aggregates from each enantiomer are capable of emitting circularly polarized light, thus enabling both right- and left-handed CPL from a single chiral material. The left- and right-handed supramolecular helical aggregates in the dried films have been characterized using spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques. These new chiral aggregation induced emission compounds could find applications in devices where CPL of opposite handedness is required from the same material and would facilitate our understanding of the formation of helical assemblies with switchable supramolecular chirality., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Although binary metal oxides with high theoretical specific capacities and power densities are widely investigated as promising anode materials for lithium-ion batteries (LIBs), their poor cycling stability and huge volume expansion largely limit their extensive application in practical electrode materials. Herein, we report a facile strategy to synthesize hollow NiCo2O4 nanowires through direct calcination of binary metal-organic frameworks (MOFs) in air. When evaluated as an anode material for LIBs, NiCo2O4 nanowires deliver a reversible capacity of 1310 mA h g-1 at a current density of 100 mA g-1 after 100 cycles. Even at a high current density of 1 A g-1, NiCo2O4 nanowires exhibit long-term cycling stability with a capacity of 720 mA h g-1 after 1000 cycles. The outstanding lithium-storage performance can be attributed to the unique structures with 1D porous channels, which are beneficial for the fast transfer of Li+ ions and electrolyte and alleviate the strain caused by the volume expansion during cycling processes.

Unmodified tripeptides and dopamine molecules can coassemble into fluorescent hybrid nanostructures, which break the intrinsic emission limit of both dopamines and peptides with an over-50 nm red-shift. We demonstrate that the coassembly method can effectively resist the oxidation of dopamine molecules, thus inhibiting their melanin pathway.