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Single-atom catalysts have attracted numerous attention due to the high utilization of metallic atoms, abundant active sites, and highly catalytic activities. Herein, a single-atom ruthenium biomimetic enzyme (Ru-Ala-C3N4) is prepared by dispersing Ru atoms on a carbon nitride support for the simultaneous electrochemical detection of dopamine (DA) and uric acid (UA), which are coexisting important biological molecules involving in many physiological and pathological aspects. The morphology and elemental states of the single-atom Ru catalyst are studied by transmission electron microscopy, energy dispersive X-ray elemental mapping, high-angle annular dark field-scanning transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. Results show that Ru atoms atomically disperse throughout the C3N4 support by Ru-N chemical bonds. The electrochemical characterizations indicate that the Ru-Ala-C3N4 biosensor can simultaneously detect the oxidation of DA and UA with a separation of peak potential of 180 mV with high sensitivity and excellent selectivity. The calibration curves for DA and UA range from 0.06 to 490 and 0.5 to 2135 μM with detection limits of 20 and 170 nM, respectively. Moreover, the biosensor was applied to detect DA and UA in real biological serum samples using the standard addition method with satisfactory results.Benefiting from specific target recognition by antibodies, the immunoassay is one of the widely used assays for the detection of biologically and environmentally important small molecules in broad fields. It can be challenge to isolate small molecules from their antibody complex in an immobilization-free immunoassay with separation for the detection of small-molecule targets. Here we present an immunoassay mediated by a triply functional DNA probe. A DNA strand is dually labeled with a fluorophore and the target small molecule. This DNA probe integrates three functions, including specific binding to the antibody, signal reporting for sensitive fluorescence detection, and carrying negative charges to facilitate capillary electrophoresis (CE) separation. The binding of the probe to an antibody brings many negative charges in the complex and causes significant changes in mass-to-charge ratios, so the antibody-probe complex can be well separated from the unbound probe in CE analysis. A simple immunoassay is achieved by target competition with this DNA probe for antibody binding in CE coupled to ultrasensitive laser-induced fluorescence (LIF) detection. To show a proof of concept, we detected two model small-molecule targets, digoxin, a therapeutic drug, and ochratoxin A (OTA), an important mycotoxin for food safety. In addition, the use of two DNA probes with distinguished migration times in CE allowed the simultaneous detection of OTA and digoxin. This immunoassay provides new opportunities for wide applications.Synthesis of solid-state proton-conducting membranes with low activation energy and high proton conductivity under anhydrous conditions is a great challenge. Here, we show a simple and convenient way to prepare covalent triazine framework membranes (CTF-Mx) with acid in situ doping for anhydrous proton conduction in a wide temperature range from subzero to elevated temperature (160 °C). The low proton dissociation energy and continuous hydrogen bond network in CTF-Mx make the membrane achieve high proton conductivity from 1.21×10-3 S cm-1 (-40 °C) to 2.08×10-2 S cm-1 (160 °C) under anhydrous conditions. Molecular dynamics and proton relaxation time analyses reveal proton hopping at low activation energies with greatly enhanced mobility in the CTF membranes.Manganese-based compounds have emerged as attractive cathode materials for zinc-ion batteries owing to their high operating voltage, large specific capacity, and no pollution. However, the structural collapse and sluggish kinetics of manganese-based compounds are major obstacles that hinder their practical applications. Here, a kind of novel layered Ca2Mn3O8 with a low ion diffusion barrier and high structural stability has been achieved through an electrochemical charging process with in situ injecting oxygen vacancies. This greatly increases the electrochemical active area and improves the Zn ions diffusion coefficient by 2 orders of magnitude, which significantly enhances the reaction kinetics, pseudocapacitance properties, and capacity. As a result, the cathode containing oxygen vacancies present an impressive reversible capacity of 368 mAh g-1, an unprecedented energy density of 512 Wh kg-1, and superior capacity retention of 92.3% at a high current density of 5 A g-1 after 3000 cycles. This work unveils an effective method for vacancy regulation of electrode materials, paving a new way to improve the electrochemical performance of zinc-ion batteries.Water dissociation in alkaline solutions is one of the biggest challenges in hydrogen evolution reactions (HERs). The key is to obtain a catalyst with optimal and balanced OH adsorption energy and H adsorption/H2 desorption energy. Herein, we synthesized a Ni17W3/WO2 catalyst on the Ni foam that optimized the coverage and size of Ni17W3 alloys decorated on the NiWO4/WO2 substrate. Our experiments showed that Ni17W3-NiWO4 interfaces could accelerate water dissociation, and Ni17W3-WO2 interfaces facilitate adsorbed H atoms spillover and H2 desorption. In addition, we applied a suite of characterization techniques to analyze surface evolution processes in catalysts under various cathodic potentials so as to illustrate the competition between chemical oxidation and electrochemical reduction reactions. The results demonstrated that high coverage of large Ni17W3 nanoparticles resulted in a greater stable interface. The two efficient interfaces synergetically promote the Volmer-Tafel reaction. Ni17W3/WO2 catalysts exhibited extraordinary HER activity with a low overpotential of 48 mV at a 10 mA cm-2 current density and a Tafel slope of 33 mV dec-1. selleck products This work has shown that low-cost catalysts with proper hierarchical interfaces can be engineered and can be optimized into a tandem system, which will significantly promote HER activity in alkaline electrolytes.