RESUMEN
In this research, we synthesized and constructed a novel gelator (namedQN) combining quinoline and naphthalene that self-assembled in N, N-dimethylformamide (DMF) to form a stable supramolecular gel (namedOQN). Under UV light, gelOQNexhibited extremely bright yellow fluorescence. The gelOQNshowed excellent sensing performance for both Fe3+and Cu2+, with a fluorescence 'turn-off' detection mechanism and the lowest detection limit of 7.58 × 10-8M and 1.51 × 10-8M, respectively. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectra, x-ray powder diffraction (XRD), rheological measurements, x-ray photoelectron spectroscopy (XPS), and fluorescence spectroscopy were used to characterize the gelOQN. TheOQNion-responsive membrane created is an excellent fluorescent writing material.
RESUMEN
In recent years, notable headway has been made in augmenting supercapacitor functioning through employment of pioneering components, exceptional nanostructures and additional investigation of electrolytes. Nonetheless, achieving superior performance with straightforward techniques remains a significant hurdle. In order to surmount this, an experimental three-dimensional nanospherical pore structure (TPB-20@Ni(OH)2) was designed and prepared. TPB-1 was obtained through carbonisation and activation. TPB-20@Ni(OH)2nanoparticles were synthesized using TPB-1 as the carbon source and nickel chloride hexahydrate as the nickel source. Furthermore, the TPB-20@Ni(OH)2//AC supercapacitor displayed an impressive energy density of 22.1 Wh kg-1. The TPB-20@Ni(OH)2composites exhibited a specific capacity of 978 F-1, which is noteworthy. The exceptional output exhibited by the TPB-20@Ni(OH)2composite derives from its innovative structure, presenting an extensive specific surface area of 237.4 m2g-1and porosity of roughly 4.0 nm. Following 20 000 cycles (at a current density of 1 A g-1), asymmetric supercapacitors assembled from TPB-20@Ni(OH)2//AC retained 80.0% of its initial specific electrostatic capacity, indicating superior electrochemical stability and high electrochemical reversibility.
RESUMEN
A new gel factor (named N) has been successfully designed and synthesized, which contains the conventional fluorophore naphthalene with the acylhydrazone bond as the self-assembly site. It can be self-assembled into stable organogels (named ON) in dimethyl sulfoxide (DMSO) and water mixed medium (V : V = 4 : 1) with a critical gel temperature and concentration (55 °C and 10 mg mL-1). Interestingly, under 365 nm UV light, the ON exhibits bright yellow Aggregation Induced Emission (AIE). The supramolecular organogel ON shows a fluorescent "OFF" response to the metal ions Fe3+, and the state of the gel ON remains constant before and after detection. Notably, the minimum detection limits (LODs) of the gel ON for Fe3+ are as low as 1.30 × 10-7 M. The binding mechanism of supramolecular organogels (ON) to ions has been investigated through a series of characterizations. Meanwhile, the organogel sensor ON can also be used as an ion-responsive membrane for the detection of Fe3+ in the aqueous phase.
RESUMEN
In this work, a mild chemical precipitation method and simple hydrothermal treatment of the nickel hexamyanocobaltate precursor strategy are developed to prepare a sea urchin-like CoNi2S4compound with remarkable specific capacity and excellent cycling stability. The prepared CoNi2S4has an outstanding specific capacity of 149.1 mA h g-1at 1 A g-1and an initial capacity of 83.1% after 3000 cycles at 10 A g-1. Moreover, the porous carbon nanospheres (PCNs) with exhibit cycling stability (94.7% of initial specific capacity after 10 000 cycles at 10 A g-1) are selected as negative electrode to match CoNi2S4positive electrode for assembly of CoNi2S4//PCNs asymmetric supercapacitor (ASC). Satisfactorily, the as-assembled CoNi2S4//PCNs ASC exhibits an impressive energy density of 41.6 Wh kg-1at 797 W kg-1, as well as the suitable capacity retention of 82.8% after 10 000 cycles. The superior properties of the device demonstrated that the as-prepared material is potential energy storage material.
RESUMEN
Synthesis of NiHCCo precursors via simple co-precipitation and nickel-cobalt tetraselenide composites grown on nitrogen-doped reduced graphene oxide (NiCoSe4/N-rGO) were fabricated using solvothermal method. The introduction of N-rGO used as a template effectively prevented agglomeration of NiCoSe4nanoparticles and provided more active sites, which greatly increased the electrochemical and electrical conductivity for NiCoSe4/N-rGO. NiCoSe4/N-rGO-20 presents a remarkably elevated specific capacity of 120 mA h g-1under current density of 1 A g-1. NiCoSe4/N-rGO-20 demonstrates an excellent cycle life and achieves a remarkable 83% retention rate over 3000 cycles with 10 A g-1. NiCoSe4/N-rGO-20//N-rGO asymmetric supercapacitor was constructed based on the NiCoSe4/N-rGO-20 as an anode, N-rGO as cathode by using 2 mol l-1KOH as an electrolyte. NiCoSe4/N-rGO-20//N-rGO ASC demonstrates an ultra-big energy density of 14 Wh kg-1and good circulation stability in the power density of 902 W kg-1. It is doubled in comparison to the NiCoSe4/N-rGO-20//rGO asymmetric supercapacitor (7 Wh kg-1). The NiCoSe4/N-rGO-20//N-rGO ASC capacity retention is still up to 93% over 5000 cycles (5 A g-1). The results reveal that this device would be a prospective cathode material of supercapacitors in actual applications.
RESUMEN
Recently, prussian blue analogues (PBAs), as the most classical class of metal-organic frameworks, have been widely studied by scientists. Nevertheless, the inferior conductivity of PBAs restricts the application in supercapacitors. In this work, nickel cobalt hexacyanoferrate (Ni2CoHCF) had been produced via a simple co-precipitation approach and coated with polypyrrole on its surface. The conductivity of PBAs was improved by the polypyrrole coating. The Ni2CoHCF@PPy-400 microspheres were demonstrated to the outstanding specific capacity of 82 mAh g-1at 1 A g-1. After 3000 cycles, the Ni2CoHCF@PPy-400 microspheres had a long cycle life and 86% specific capacity retention rate at 5 A g-1. Additionally, it was coupled with activated carbon to build high performance asymmetric supercapacitor (Ni2CoHCF@PPy-400//AC), which displayed a high energy density of 21.7 Wh kg-1at the power density of 888 W kg-1and good cycle stability after 5000 cycles (a capacity retention rate of 85.2%). What is more, the results reveal that the Ni2CoHCF@PPy-400 microspheresare a prospective candidate for exceptional energy storage devices.
RESUMEN
A novel gelator molecular based on quinolone (MN) has been successfully designed and synthesized. The gelator MN could self-assemble to form a supramolecular gel (OMN), which showed obvious aggregation-induced emission (AIE) in iso-Propyl alcohol (i-PrOH). Furthermore, the supramolecular organogel OMN realized ultrasensitive detection of Fe3+ and Cu2+ in aqueous medium and fluorescent quenching at 427â¯nm. The sensing mechanism between supramolecular gel and metal ions was fully investigated via FE-SEM, FT-IR, XRD and XPS. Meanwhile, a thin film based on responsive supramolecular gel OMN was prepared, which could be used as multi-stimuli-responsive fluorescent display materials for the detection of Fe3+ and Cu2+.
Asunto(s)
Quinolinas , Iones , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this work, an anchored Pd complex (PGS-APTES-Pd(OAc)2) was prepared via simple and green steps from the natural clay mineral palygorskite and was well characterized by XPS, XRD, IR, SEM, and EDX. This complex was further utilized as a fine catalyst for the C-C/C-N coupling reactions of pyrimidin-2-yl sulfonates. Subsequently, the cyclic utilization test indicated the high stability and sustainability of this PGS-APTES-Pd(OAc)2 catalyst, and no activation was required in the recycling process, providing an applicable and reusable catalyst in organic synthesis.