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Artificial enzymes with high stability, adjustable catalytic activity, controllable preparation, and good reproducibility have been widely studied. Noble metal nanozymes, particularly gold nanoparticles (Au NPs), exhibit good catalytic activity, but their stability is poor. In this study, zeolitic imidazolate framework-8 (ZIF-8) was used as a carrier for Au NPs, thus improving the utilization efficiency and conservation stability of the nanozymes. A ZIF-8/Au nanocomposite with peroxidase activity and a raspberry-shaped structure was synthesized. In the assay, ZIF-8/Au catalyzed the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to a blue product oxidized TMB (oxTMB). Glutathione (GSH) selectively inhibited this reaction, with a detection limit of 0.28 µM and linear range of 0.5-60 µM. Using the photo and chromaticity analysis functions, we developed a portable analysis method using a smartphone equipped with a camera module as a detection terminal for a wide range of rapid screening techniques for GSH. Preparation of raspberry-shaped ZIF-8/Au improved the catalytic activity of Au NPs and good results were demonstrated in serum, which suggests their promising application under physiological conditions., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Even though some recent research revealed individuals with HSA typically display enhanced processing in the early stages of emotional information processing due to hypervigilance and vulnerability to negative stimuli, it is still unclear whether social anxiety affects the time course underlying processing bias for emotional stimuli. Therefore, the present study aimed to explore the early stage of processing social threat stimuli in high social anxiety (HSA) individuals by recording RTs and EEG data in the emotional Stroop task. Behavioral data showed that the HSA group responded to the threat words faster than neutral words (i.e. negative bias), but no emotional effects in the low social anxiety (LSA) group. Although the P1 component did not show any early effects, ERP data exhibited an enhanced N170 for HSA than for LSA groups. Threat words elicited larger N170 than neutral words in the LSA group only; this emotion effect was not evident in the HSA group. These findings indicated that social anxiety modulates early processing for social threat words. This study revealed the neural mechanisms underlying early emotional processing in individuals with social anxiety, providing insights for the evaluation and intervention of social anxiety.

The precisely modulated synthesis of programmable light-emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene-based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation-induced electrochemiluminescence (PI-AIECL) systems. The best-performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2'-bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six-fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL-based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high-performance aggregation-induced electrochemiluminescence emitters., (© 2023 Wiley-VCH GmbH.)

Potassium-ion batteries (PIBs) have attracted enormous attention due to the increasing lithium battery cost, but their development is still in the pre-mature stage due to the limited selection of electrodes. Herein, a free-standing current-collector-integrated electrode, composed of mixed-phase WS 2 nanosheets with nitrogen-doped multichannel carbon nanofibers (N-MCNFs) membrane, is reported for high-performance potassium ion batteries anode. Benefiting the unique multichannel carbon nanostructure as a current collector-integrated electrode as well as mixed-phase lamellar structure WS 2 for enhanced potassium ion entry, the 1T/2H-WS 2 /N-MCNFs hybrid current-collector-free anode delivers an outstanding areal capacity of 2.88 mAh cm -2 (corresponding to 411 mAh/g based on the mass of both electrode and current collector) at a current of 0.7 mA cm -2 as well as long-term cycling stability for over 1000 cycles at a high current of 14 mA cm -2 , surpassing the current state-of-art PIB anode. It is believed that our findings based on the high energy current collector integrated electrode at high mass loading would boost future research on practical metal ion batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Owing to their almost similarities in size, shape, and chemical reactivity, effectively distinguishing deuteroxide (D 2 O) in water (H 2 O) remains an ongoing challenge, and the examples of a D 2 O probe are still quite scarce. Herein, since H 2 O can decrease the lifetime of a singlet oxygen as a vital intermediate and an H/D exchange in the luminescence process of porphyrins, we systematically investigated the enhanced ultraviolet-visible (UV-vis), photoluminescence (PL), and electrochemiluminescence (ECL) of water-soluble tetrakis(carboxphenyl)porphyrin (TCPP) in D 2 O. The findings showed that these luminescent properties had been greatly enhanced with the increase of the D 2 O fraction in water. Consequently, we first developed the highly facile methods of detecting D 2 O in H 2 O by the UV-vis, PL, and ECL of TCPP, respectively. Impressively, the ECL analysis exhibited a great superiority with a lower detection limit of 0.29 nM. The work not only achieves the challenging task of distinguishing between H 2 O and D 2 O but also provides a unique strategy to enhance the luminescent performance of porphyrin.

We have designed and synthesized three novel benzo[de]isoquinoline-1,3-dione (BQD) condensed asymmetric azaacenes, BQD-TZ, BQD-AP and BQD-PA, with different end groups of 1,2,5-thiadiazole, acenaphthylene and phenanthrene. The triisopropylsilylethynyl groups were grafted to increase the solubility and crystallinity of the three molecules. These molecules have high electron affinity values of 3.87, 3.69 and 3.74 eV for BQD-TZ, BQD-AP and BQD-PA, respectively as confirmed by cyclic voltammetry measurements. Single-crystal X-ray diffraction revealed that these molecules have strong π-π stacking with distances of 3.31-3.41 Å and different stacking arrangements., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Super-resolution microscopy (SRM) imaging of the finite subcellular structures and subtle bioactivities inside organelles delivers abundant cellular information with high fidelity to unravel the intricate biological processes. An ideal fluorescent probe with precise control of fluorescence is critical in SRM technique like stimulated emission depletion (STED). Si-rhodamine was decorated with both targeting group and H + -receptor, affording the dually fluorogenic Si-rhodamine in which the NIR fluorescence was efficiently controlled by the coalescent of spirolactone-zwitterion equilibrium and PeT mechanism. The dually fluorogenic characters of the probe offer a perfect mutual enhancement in sensitivity, specificity and spatial resolution. Strong fluorescence only released in the existence of targeting protein at acidic lysosomal pH, ensured precisely tracking the dynamic of lysosomal structure and pH in living cells by STED., (© 2021 Wiley-VCH GmbH.)

To obtain a highly active, stable, and binder-free electrode based on transition-metal compounds for water splitting, nickel foam-supported 3D NiMoO 4 nanosheet arrays modified with 0D Fe-doped carbon quantum dots (Fe-CQDs/NiMoO 4 /NF) are synthesized. The structure characterizations indicated that 0D Fe-CQDs are evenly dispersed onto the NiMoO 4 sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe-CQDs are deposited 3D on the NiMoO 4 sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe-CQDs/NiMoO 4 /NF catalysts. At a current density of 10 mA cm -2 , the resultant Fe-CQDs/NiMoO 4 /NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface., (© 2020 Wiley-VCH GmbH.)

Developing a convenient and rapid detection method for water is greatly desirable in the field of chemical industry. Herein, we present a simple and effective strategy combining a fluorescence sensor and a one-to-two fluorescence colorimetric logic operation to monitor water in a wide range of organic media and classify aprotic/protic polar solvents. The dual-emitting luminescent detector was prepared by incorporating a fluorescent dye Rhodamine 6G (R6G) with strong green light emission within a red light-emitting Eu-metal-organic framework (MOF) through the "bottle around ship" method. R6G@Eu-MOF displays completely different fluorescence response behaviors to various organic solvents. Thus, when one made use of the intensity ratio of different fluorescence emission centers, a 3D decoded map was proposed to reliably and effectively distinguish different aprotic/protic polar solvents. Moreover, R6G@Eu-MOF exhibited two different ratiometric sensing modes when detecting water in aprotic/protic polar solvents due to the hydrogen bonding interaction, that is ratiometry with one reference signal or two reversible signal changes. Furthermore, using water content as the input signal and two kinds of fluorescence emission as the output signals, a one-to-two logic gate system was constructed, making it possible to develop an intelligence system for water detection. Overall, we demonstrated for the first time that R6G@Eu-MOF could serve as an efficient platform for tracing water in organic media and distinguishing protic/aprotic polar organic solvents.

The metal-organic framework (MOF-74) series has the most open metal sites. The metal ions have different bonding strengths with the ligand in MOF-74 and the bond of the ligand can be successively broken to obtain highly active heteroparticles by controlling the temperature, which is difficult to achieve using traditional methods. Magnetic NiCo/Fe3O4-MOF-74, which is fabricated using trimetallic NiCoFe-MOF-74 as a precursor, is simple and rational in comparison with the traditional magnetic core and tunable MOF shell hybrid composites that are formed using a step-by-step assembly strategy. After thermal treatment under a specific atmosphere, NiCo/Fe3O4-MOF-74 shows higher stability, strong magnetism and more active metal sites compared to the original MOF. NiCo/Fe3O4-MOF-74 shows excellent enrichment capability for the removal of tetracycline, with a high removal efficiency that reached 94.1% within 5 min, which is much higher than that of NiCoFe-MOF-74. The main interaction between the adsorbent and analyte is most likely attributed to the open metal sites that can form a stable metal-ligand with the antibiotic molecules. Furthermore, the material can be reused five times without considerable loss. The prepared material has potential applications for removing antibiotics with high efficiency at low cost. Therefore, the experiments described in this study provide a route to a broad class of MOF-based materials for detecting organic contaminants.

The development of highly active, eco-friendly, and structurely fine-tunable organic luminophores is currently desirable for electrochemiluminescence (ECL). Tetraphenylethene (TPE) derivatives are the most representative aggregation-induced emission characteristic (AIEgens). In contrast, their aggregation-induced ECLs have not been detail studied. Herein, we report the bright cathodic aggregated state ECL of TPE derivatives by a coreactant approach. In this system, the substituents profoundly affect ECL emissions by changing the relative intensities of R and B band intensity ratios in their UV-vis spectra as well as the HOMO and LUMO energies. It was discovered that electron-withdrawing nitro-substituted TPE-(NO 2 ) 4 with a smaller LUMO/HOMO band gap and stronger R band featured the strongest ECL emissions and became the best luminophore for the highly efficient detection of iodide (I - ) in the aqueous phase. This work not only reveals the influence of R and B bands in TPE derivative UV-vis spectra on their optical properties but also constructs a novel aggregation-induced ECL sensing.

Highly efficient detection in the aqueous phase for water-insoluble organic molecule probes is challenging. The bright aggregated-state electrochemiluminescence (ECL) of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles by a co-reactant approach was discovered, and a heterogeneous aggregation-induced emission ECL (HAIE-ECL) was constructed at the electrode surface, showing very high ECL efficiency (37.8 %) and selective recognition for industrially important DNBP plasticizer with a low detection limit of 0.15 nm in the water phase. A mechanistic study indicates that ECL is mainly generated due to the high electron affinity of siloles and restriction of the intramolecular motions caused by their propeller-like noncoplanar structures. This system realizes the sensing of organic-based ECL in the water phase by solving the crucial problems of water insolubility and aggregation-caused quenching (ACQ), and demonstrates potential for further application because of its design and high efficiency., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, a metastable aqueous interface was fabricated for synthesizing mesoporous and high surface area MnO 2 . When urea was used as the additive, hierarchical spheres self-organized from ultrathin nano-sheets were obtained. Its porous structure could be controlled through adjusting the urea concentration, and a maximum surface area of 407m 2 g -1 was achieved by this method, which is larger than the reported values. Due to the porous structure and high surface area, as-prepared MnO 2 exhibited a specific capacitance of 775.4 F g -1 at a current density of 0.1 A g -1 , and exhibited a 63.5% capacitance retention when the current density was increased from 0.1 A g -1 to 5A g -1 . Durability studies showed a 63.7% capacitance retention after 2500 cycles. The metastable interfacial reaction approach could also be extended to other alloys with large surface area and porous structure, such as CoB alloy. This method provides a simple and low-cost method to synthesize high surface area and mesoporous materials., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Based on an Eu-PB modified platinum electrode as the working electrode, a method for the simultaneous determination of the four tropane alkaloids, anisodamine, scopolamine, atropine and anisodine, by capillary electrophoresis with electrochemiluminescence detection (CE-ECL) has been established. The effects of several factors, such as the detection potential, the acidity and concentration of the running buffer, and the content of the methanol additive were investigated for the improvement of separation ability and detection sensitivity. Under the optimized conditions, these four components could be fully separated from each other in a 20 mmol/L phosphate (pH 8.0) containing 7% (v/v) methanol buffer within 6 min. The relative standard deviations of the peak area and migration time were less than 5.0% and 1.1% (n = 12) respectively for all the four compounds. Thus, the method has been successfully applied to the determination of anisodamine, scopolamine in Przewalskia tangutica Maxim. The average amounts of 27.8 g/kg anisodamine and 4.43 g/kg scopolamine were found in the herbal root-stalk sample. The recoveries of the tropane alkaloids were 97.8% - 102%.