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In the realm of photocatalysis, effectively utilizing solar energy, especially the near-infrared (NIR) spectrum, presents substantial challenges. To tackle this issue, a novel composite of NaYF4:Yb3+/Er3+@Cu2O@MoS2@Fe3O4 (denoted as NYE@Cu2O@MoS2@Fe3O4) was ingeniously fabricated and assessed for the photodegradation of organic contaminants. By harnessing the distinct properties of upconversion materials, narrow bandgap semiconductors, and magnetic substances, the NYE@Cu2O@MoS2@Fe3O4 catalyst possesses a photodegradation rate of 92% for the rhodamine B dye under NIR light radiation, which is superior to NYE@Cu2O (50%) and NYE@Cu2O@MoS2 (85%). The enhanced performance in the near-infrared photocatalysis of NYE@Cu2O@MoS2@Fe3O4 is mainly attributed to the synergistic effect of various components, which promotes an increase in photo-induced carrier generation and facilitates their efficient transfer and energy utilization under NIR irradiation. This study provides a possible route for the near-infrared photocatalytic degradation of pollutants in areas with limited light or even dark conditions. [ABSTRACT FROM AUTHOR]

Owing to the advantages of easy separation and recovery, the development of magnetic photocatalysts is essential to create a viable photocatalytic technology for the degradation of antibiotic contaminants in water. Herein, magnetic Fe3O4@TiO2–Co nanocomposites as a highly recyclable and effective photocatalyst with various Co loading percentages were successfully prepared via a facile route and evaluated for the photodegradation of model tetracycline (TC) antibiotics. As a result, the optimal Fe3O4@TiO2–Co-2.7 sample possesses a removal rate of 92.4% for TC degradation, which is 3.2 fold and 1.6 fold higher than those of single Fe3O4 (28.8%) and Fe3O4@TiO2 (58.7%), respectively. The enhanced photocatalytic activity is mainly attributed to the advantages of integrating magnetic Fe3O4 nanospheres and metal Co nanoparticles, resulting in the overall magnetic composites of Fe3O4@TiO2–Co having an ameliorative light collection ability, energy-saving recycling process, excellent photocatalytic activity, and high chemical and environmental stability. Satisfactorily, the Fe3O4@TiO2–Co photocatalyst could be easily recovered from the reaction solution by an applied magnetic field, and its photocatalytic activity shows almost no loss after five cycles of repetitive use. Moreover, the intermediates in the degradation pathway were identified via high-performance liquid chromatography–mass spectrometry (HPLC-MS) and the TC degradation pathway in the photocatalytic reaction of the as-designed system was proposed. The present work was successfully applied for the purification of tetracycline antibiotics in water pollutants, demonstrating a promising prospect for application to other pollutant degradation systems. [ABSTRACT FROM AUTHOR]

A multifunctional undecapeptide, YYDPLGLADYY, was designed and synthesized for the photowrapping of silica-coated gold nanorods. The obtained nanocapsules, bearing a well-defined core–shell structure, were able to encapsulate a therapeutic drug, respond to an MMP-upregulated tumor microenvironment, and achieve NIR-triggered anticancer chemo-photothermal therapy with favorable efficacy. [ABSTRACT FROM AUTHOR]

We report a multi-stimuli-responsive luminescent material containing rotor moieties. It forms two types of crystals, G and O. The emission of G can be modulated by multiple external stimuli, whereas O does not show such responsiveness. The X-ray structure analysis reveals that the rotors are critical for the polymorphic emission and stimuli response properties. [ABSTRACT FROM AUTHOR]

The hydrogen peroxide (H2O2) levels in living organisms and environment have strong effects on many biological processes inducing cell apoptosis/cell necrosis and wound disinfection. Therefore, it is important to have an accurate and in situ detection of H2O2. Herein, an AuPd@FexOy nanozyme-based electrochemical (EC) sensor (termed as AuPd@FexOy NPs/GCE) with good stability and anti-interference ability has been prepared for the detection of H2O2 by differential pulse voltammetry (DPV) and chronoamperometry dual-measurement modes. The AuPd@FexOy NPs/GCE exhibits good linear relationships in the ranges from 13.0 to 6.0 × 103 μM (DPV measurement) and 50 to 1.0 × 103 μM (chronoamperometry measurement), low detection limits (LODs) of 1.6 μM (DPV measurement) and 3.0 μM (chronoamperometry measurement) and high sensitivities of 83.8 nA μM−1 cm−2 (DPV measurement) and 120.7 nA μM−1 cm−2 (chronoamperometry measurement). The practicability of the as-prepared AuPd@FexOy NPs/GCE has been demonstrated by an in situ real-time detection of H2O2 released from adherent living MCF-7 cells triggered by varying amounts of N-formyl- L -methionyl- L -leucyl- L -phenylalanine (FMLP) from 0.5 to 3.0 μM and the quantitative determination of H2O2 in commercial disinfectants. [ABSTRACT FROM AUTHOR]

Electrocatalytic preparation of 2,5-furancarboxylic acid (FDCA) from biomass-derived 5-hydroxymethylfurfural (HMF) is a highly attractive strategy for the development of the bio-renewable polymer industry. However, developing highly efficient catalysts with sufficient oxidation current density and durability remains a challenge. Introducing heteroatoms into layered double hydroxides (LDHs) can modulate the electrocatalysis behavior effectively. Herein, vanadium and cobalt were co-doped into nickel (oxy)hydroxide to construct a NiVCo-LDHs catalyst. With the diatomic synergetic modulation, the as-designed NiVCo-LDHs can electrosynthesize FDCA from HMF at a low potential of 1.376 V vs. RHE and achieve a 93.2–99.7% yield and 86.5–97.8% faradaic efficiency of FDCA during ten consecutive cycles. Such performance is superior to those of most reported nickel-based LDHs for HMF oxidation. Further studies indicate that the introduction of V can provide high intrinsic catalytic activity, mainly due to the enhanced specific surface area, facile electron transfer and abundant active sites. [ABSTRACT FROM AUTHOR]

We report J-aggregates of a boron dipyrromethene derivative (BDP-Nit) as an H2S-activatable nano-photosensitizer. The closely packed BDP-Nit in J-aggregates exhibits high selectivity to H2S over biothiols to produce an active photosensitizer. [ABSTRACT FROM AUTHOR]

3,4-Methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) are the main components of illicit stimulant drugs, also known as "ecstasy", which belong to psychoactive medicine and tend to be increasingly abused among drug addicts worldwide. Herein, an electrochemical sensor based on molecularly imprinted polydopamine (MIP@PDA) was developed to detect MDA and MDMA using differential pulse voltammetry (DPV). An MIP film on a Au electrode was synthesized via electrochemical polymerization with the safe chemical DA as the polymerization monomer and the uncontrolled pharmaceutical intermediate 3,4-methylenedioxyphenethylamine (MDPEA) as the template molecule, which can provide a great quantity of specific binding sites and expand the practical application of the sensor. Due to the superior affinity of MIP@PDA to the target, the proposed sensor displayed excellent analytical performance, with LODs of 37 nM and 54 nM for the determination of MDA and MDMA, respectively. Additionally, this sensor presented suitable selectivity, stability, reproducibility and detection ability in practical urine samples, which suggested that it is a promising candidate as a rapid diagnostic method in drug investigations. [ABSTRACT FROM AUTHOR]

The production of reactive oxygen species (ROS) leads to the generation of oxidative stress, which will result in the excessive production and accumulation of melanin in the body and even the occurrence of some skin diseases. The intervention of antioxidants can slow down the rate of melanin formation to some extent. In order to explore the relationship between ROS, melanin and antioxidants, this work investigated the effects of antioxidants on melanin formation by the scavenging of ROS in vitro, where zebrafish were used as the model organism in in vivo experiments. The results showed that the inhibition order of natural antioxidants on melanin formation was GSH > AA > GA and PG > BHT > BHA for synthetic antioxidants. Between natural antioxidants and synthetic antioxidants, the former mainly have a strong scavenging ability on ˙OH and 1O2, while the latter have a strong scavenging ability on O2˙−. At the same time, the results in vivo showed that GSH and PG within a certain concentration not only did not affect the hatchability, survival rate and teratogenic rate of zebrafish embryos, but also can significantly inhibit melanin formation in zebrafish embryos. The results of this study have an important guiding significance for the dosage of antioxidants used in the cosmetics and food industries. [ABSTRACT FROM AUTHOR]

To achieve the most efficient, all-exciton-harvesting organic electrochemiluminescence (ECL) for biosensing, aqueous thermally activated delayed fluorescence (TADF)-ECL (aqueous TADF-ECL) was successfully launched to provide a breakthrough for the theoretical ECL efficiency limitation of aqueous fluorescence ECL (aqueous FL-ECL). However, achieving efficient TADF emitters suitable for aqueous TADF-ECL remains challenging. A previous strategy relied on TADF small molecular nanoparticles (NPs). However, the aggregation caused quenching of such TADF molecules within NPs is intense, which renders such NPs inefficient for ECL emission. Herein, we propose developing conjugated polymer dots (Pdots) based aqueous TADF-ECL. Compared to the intrinsic TADF polymer, the Pdots achieve a comparable TADF photophysical properties in water, i.e., the comparable PL spectra, similar PL quantum efficiency (ΦPL) and intense delayed fluorescent contributions via a fast reverse intersystem crossing rate (kRISC) of 1.5 × 106 s−1. The resultant relative ECL efficiency (ΦECL) of the oxidative-reduction ECL system (C2O42− as the co-reactant) is as high as 11.73% (vs. the Ru(bpy)32+ counterpart). Additionally, satisfactory dopamine biosensing was accomplished for such TADF-Pdots/C2O42− couple. All those results are combined to highlight the promising potential of such an aqueous TADF-ECL strategy. [ABSTRACT FROM AUTHOR]

Enzyme-based sensing platforms have undergone rapid development in the field of diagnosis and bioanalysis. Here we present a novel fluorescent artificial enzyme-based detection strategy for L -cysteine (Cys) and H2O2 by fabricating a series of Au–Ag bimetallic nanoparticles with peroxidase-like activity. Taking advantage of the enhanced performance of catalysts by optimizing the surface structure, the sensitive detection of Cys with an ultralow detection limit of 0.035 μM and accurate quantification in the range of 0.075–2 μM were achieved. It was revealed that the mechanism of the catalytic process on the Au–Ag surface follows the electron transfer mechanism rather than active species, that is the peroxidase-like catalysts work as electron transfer intermediates and the electron transfer efficiency will increase with the larger electron cloud density of active sites derived from the electronic synergistic effect between Au and Ag, contributing to the enhanced catalytic activity of peroxidase mimics. This finding could provide guidance for the structural design of high-activity peroxidase mimics. [ABSTRACT FROM AUTHOR]

We report N,O-boron-chelated dipyrromethene derivatives exhibiting circularly polarized luminescence (CPL) in the red/near-infrared region, both in solution and the aggregated state. The CPL is originated from the helical chirality through intramolecular substitution of fluorine by an alkenolic substituent. The self-assembly of the fluorophores significantly enhances the ‖glum‖ values from 10−4 to 10−2. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are receiving increased attention due to their cost-effective and similar energy-storage mechanism to lithium-ion batteries. Metal selenides have been widely studied owing to their relatively high theoretical capacity. However, requirements for high capacity and excellent rate capability have been still an urgent challenge for energy storage systems. To address such issues, we report mesoporous N-doped carbon-coated CoSe nanocrystals encapsulated in S-doped carbon nanosheets (CoSe-SC@NC) as advanced anode for SIBs. In such a design, CoSe nanoparticles are evenly distributed among the carbon nanosheets, alleviating the volume expansion and maintaining the structural integrity. S/N-doping and mesoporous carbon coating improve electronic conductivity and accelerate ion transfer. Therefore, CoSe-SC@NC exhibits an ultrahigh initial coulombic efficiency (92.4%), high sodium storage capacity (505.4 mA h g−1 at 0.2 A g−1 after 100 cycles), and superior long cycling stability at 1 A g−1 (capacity retention of 412.2 mA h g−1 after 1336 cycles), as well as ultrathin and robust solid electrolyte interphase. Ultimately, the full cell is assembled and delivered a remarkable capacity of 98.7 mA h g−1 at 2C rate. Moreover, the improved sodium storage mechanism is further analyzed by in situ X-ray diffraction and ex situ transmission electron microscopy. [ABSTRACT FROM AUTHOR]

The development of carbon nanomaterials, which have the merits of being based on an abundant resource and environmentally friendly, as stabilized rechargeable ion battery anodes faces enormous challenges due to the limited interlayer spacing and sluggish kinetics. Herein, we synthesized high-yield two-dimensional N/O co-doped porous turbostratic carbon nanomeshes (NOPTCs) with an ultralarge interlayer spacing (0.434 nm) and abundant edge defects via a combination copolymerization and carbonization strategy. Benefiting from its structural properties, the optimized NOPTC-700 achieves remarkable electrochemical performance as an anode material for both potassium-ion (292.8 mA h g−1 at 1 A g−1 after 1000 cycles and 219.0 mA h g−1 at 2 A g−1) and lithium-ion (466.7 mA h g−1 at 2 A g−1 after 2000 cycles) batteries. The underlying potassium-ion storage mechanism was clarified via detailed ex situ Raman analysis, which indicated a highly reversible ion insertion and extraction process. First-principles calculations further prove that the sufficient defects and reactive sites induced by heteroatom N/O co-doping contribute synergistically to the excellent electrochemical performance of the NOPTCs. The NOPTC-700 delivers outstanding full cell performance coupled with a potassium Prussian blue (KPB) cathode in potassium-ion batteries (PIBs) as well as with a commercial LiFePO4 (LFP) cathode in lithium-ion batteries (LIBs), exhibiting great potential and broad prospects in practical applications. [ABSTRACT FROM AUTHOR]

Endogenous H2O2 generated by a single HeLa cell that was adhered on the PDA-coated PDMS substrates under 25 mM glucose culture conditions was detected using a home-built photoelectric dual detection platform. With PMA as the stimulus, the cell released a small amount of H2O2 and its mitochondrial membrane potential (MMP) decrease was smaller, compared with that on the PDMS substrates. [ABSTRACT FROM AUTHOR]

Low-cost and eco-friendly hole-transport materials (HTMs) are exceedingly desirable for the practical application of perovskite solar cells (PVSCs). Here, a traditional bidentate ligand (1,10-phenanthroline), widely used as a chelating agent for bioorganic reagents and probes, is incorporated into an HTM to afford M1. Such a planar bidentate ligand at the central core of the HTM can facilitate π–π stacking and enable chelation to Pb2+ ion defects and thus achieve efficient passivation at the M1/perovskite interface, contributing to reduced recombination loss. When employed as an HTM in inverted PVSCs without dopants, bidentate-ligand-based M1 yields a high power conversion efficiency (PCE) of 20.14%, which is significantly higher than that (18.32%) of the M0 analogue that contains phenanthrene. More importantly, green solvent processing (ethyl acetate) of M1 achieves a PCE of 19.21%, which is among the highest values reported in PVSCs with a green-solvent-processable HTM. Besides, the facile one-step synthesis route reduces the cost to 45 $ gram−1 for M1, which is cheaper than the most reported HTMs for high-efficiency PVSCs without dopants. These findings demonstrate the potential of bidentate ligands in developing cost-effective and eco-friendly HTMs toward highly efficient PVSCs. [ABSTRACT FROM AUTHOR]

A nanoencapsulation strategy is introduced to a state-of-the-art thermally activated delayed fluorescence (TADF) molecule, i.e. 4CzIPN, which ensures the achievement of air-stable, water-soluble TADF nanoparticles featuring efficient TADF property without an unsatisfactory oxygen quenching effect. Accordingly, we report here for the first time the electrochemiluminescence of TADF emitters in aqueous media. [ABSTRACT FROM AUTHOR]

Photodriven CH4 conversion has been regarded as a promising green strategy for fabrication of value-added commodity chemicals, in particular methanol. However, due to the incomplete transformation of intermediates or the overoxidation of products, a good selectivity of methanol is hard to achieve. Here, we present a highly selective transformation of methane to methanol using gold modified zinc oxide as a photocatalyst under full light spectrum irradiation at atmospheric temperature. The selectivity of methanol can reach 99.1% with a productivity of 1371 μmol g−1. Fine tuning the loading amount of gold nanoparticles (0.75 wt%) and inputting an appropriate light energy are the pivotal factors for selectivity improvement. Besides, in contrast to the reported photocatalytic aerobic CH4 oxidation on gold modified zinc oxide, we find that both oxygen and water, rather than only molecular oxygen, provide the O-source for methanol formation. This result is verified through 18O-isotope tests (18O2 and H218O), leading to a disparate mechanism. [ABSTRACT FROM AUTHOR]

We report a series of difluoroboron β-diketonate fluorophores that manifest temperature-dependent emission wavelength accompanied by a change of fluorescence from green to orange. The distinct emission changes allow convenient and accurate measurements of temperature. [ABSTRACT FROM AUTHOR]

Controlled/"living" radical polymerization (CLRP) techniques, such as atom transfer radical polymerization (ATRP), reversible addition–fragmentation chain transfer (RAFT) polymerization, and their variants, have now emerged as a novel class of signal amplification strategies and they have attracted growing attention in biosensing of clinically relevant biomolecules. Through the CLRP-mediated de novo formation of polymer chains, a large amount of signaling probes (e.g., ferrocene) or functional groups (e.g., –NH2, –CHO, and –COOH) that are available for the subsequent introduction of signaling probes can be recruited in the sensing interfaces, outputting a high signal even in the presence of a low abundance of target analytes, thereby greatly improving the detection sensitivity. Compared with conventional strategies based on the use of either catalytic labels (e.g., natural enzymes, biomimetic catalysts, and electrocatalysts) or complex nanomaterials (e.g., surface-functionalized metal nanoparticles), CLRP-based signal amplification strategies have advantages of being low-cost, highly efficient, and relatively easy in operation. By virtue of these merits, CLRP-based signal amplification strategies show great promise for clinical applications and biomedical research studies. In this review, the advantages and disadvantages of various signal amplification strategies have been summarized. Following a brief introduction of the mechanisms of various CLRP techniques, a comprehensive overview of the applications of CLRP-based signal amplification strategies in biosensing of clinically relevant biomolecules such as nucleic acids, enzymes, and antigens is presented. Also discussed herein are the advantages and disadvantages of CLRP-based signal amplification strategies, which are believed to be instructive for their broad application in biosensing. [ABSTRACT FROM AUTHOR]

SO2, an important gasotransmitter, plays significant roles in human physiological activities. The reported probes for the detection of SO2 derivatives are mostly based on the quenching or blue-shift of fluorescence, leading to interference from the background signal. Herein, we develop a novel FRET-based nanoprobe that shows turn-on fluorescence at 615 nm in the presence of SO32−/HSO3−. The nanoprobe consists of N,O,B-chelated dipyrromethene (BDP) as the energy donor, and hemicyanine derivatives of HEM-CO-Ph with a responsive site to SO32−/HSO3− as the energy acceptor. Initially, the fluorescence of BDP is quenched by HEM-CO-Ph due to the efficient FRET process. In the presence of sulfites, the nucleophilic addition interrupts the conjugation of HEM-CO-Ph and results in a 200 nm blue-shift of the absorption, leading to the suppression of the FRET process and recovery of the red fluorescence of BDP. The nanoprobe shows fast response to SO32−/HSO3− with high selectivity, great biocompatibility and cellular uptake. It is the first supramolecular nanoprobe for the detection of SO32−/HSO3− by using intermolecular energy transfer, ingeniously turning the nanoprobe from "OFF" state to "ON" state. The nanoprobe is applied to monitor exogenous and endogenous SO2 derivatives in the mitochondria of living cells. [ABSTRACT FROM AUTHOR]

We report an unexpected coupling–reduction tandem reaction as a general and efficient one-pot synthesis of alkenyl-substituted boron dipyrromethene (BODIPY) from chlorinated-BODIPY and alkyne. This unique synthesis combined the Sonogashira coupling reaction and reduction reaction without adding an additional reagent, which shows higher yields, broader substrate scope and faster reaction rate compared with the conventional methods of the Knoevenagel reaction and Heck coupling reaction. [ABSTRACT FROM AUTHOR]

We report a series of organic fluorophores that undergo selective self-sensitized photooxidation upon light irradiation in air accompanied by a change of fluorescence from yellow to blue on the seconds timescale. The distinct emission changes allow the ratiometric quantitation of O2 concentration. [ABSTRACT FROM AUTHOR]

Conversion of CO2 into valuable chemicals can not only reduce the amount of CO2 in the atmosphere, but also realize the reuse of resources. It's well known that C–O bond activation and splitting are critical steps in the CO2 conversion process and it's crucial to employ an appropriate catalyst. Here, the adsorption and activation behaviors of a CO2 molecule on 4H-SiC surfaces were systematically investigated based on DFT calculations. Calculation results show that the CO2 molecule can anchor on 4H-SiC(0001) and (0001̅) surfaces. On the 4H-SiC(0001) surface, the adsorbed CO2 molecule prefers to dissociate with an energy barrier of 0.52–0.70 eV, producing an O adatom and a CO molecule on the surface. Further dissociation of the CO is hindered due to a large energy barrier of 2.12 eV. However, if a H atom is introduced, the CO molecule may combine with H into a CHO group and the reaction energy barrier is 1.69 eV. Moreover, the CHO group tends to transform into a CH group and an O adatom, a reaction in which a relatively low energy barrier of 0.09 eV needs to be surmounted. For the 4H-SiC(0001̅) case, the direct C–O bond dissociation energy barrier for CO2 is only 0.37 eV while further breaking of the C–O bond in CO is energetically unfavorable even with the help of a H atom. So the final products are an O adatom and CO chemisorbed on the 4H-SiC(0001̅) surface. All the calculation results demonstrate that the inert CO2 molecule can be effectively activated on both the 4H-SiC(0001) and (0001̅) surfaces and different splitting products could be obtained on the two different surfaces, implying that SiC is an applicable catalyst material for CO2 conversion with high efficiency and product selectivity. [ABSTRACT FROM AUTHOR]

We report a new molecular design for optically triggered nm-scale translation of a submolecular component relative to another. We used a rotaxane-like molecule terminated at one end with stiff stilbene that served both as a chromophore to trigger the translation of the pillar[5]arene “wheel” and as a stopper to prevent its dethreading. [ABSTRACT FROM AUTHOR]

Artificial light-harvesting nanoparticles were prepared from supramolecular polymers comprised of pillar[5]arene with anthracene-derived donors and acceptors through host–guest interactions. The resulting water-dispersible nanoparticles displayed efficient energy transfer and excellent light harvesting ability in part because the steric bulk of pillar[5]arene suppressed the self-quenching of the chromophores. [ABSTRACT FROM AUTHOR]