查看更多>>摘要：In this study, we firstly introduce an ultra-high sensitive V3.6Mo2.4O16-chitosan (MV-CHT) nanocomposite for electrochemical hydroxychloroquine sulfate (HCQ) monitoring toward paracetamol (PCM) and pantoprazole (PPZ) in environmental and clinical diagnostics. The single-phase MV nanostructures are prepared via the sol-gel pechini route, followed by engineering maleic acid as a structure-directing agent. The stabilization of the MV electro-catalysts is adopted by varying critical factors such as calcination temperature, different chelating ligands, chelating molality and cross-linker concentration. The structural and morphological characterizations, namely, ordered active sites, structural integrity, porous network and dispersibility on the cationic polymer are confirmed by physicochemical analyses. Also, analytical nature of the MV-CHT modified carbon paste electrode (MV-CHT/CPE) is constructed via electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) techniques. As a result, the nano-MV-CHT/CPE platforms with 10% of polymeric matrixes delivered the boosted analytical performance in terms of linear ranges (0.0019-194.0 mu M), lower detection limit (LOD = 0.224 nM), together with excellent sensitivity and selectivity. The novel combination of MV nanoparticles and CHT provide the fluent channels for rapid charge transport and effective surface area. Such results illustrate the synergistic and interaction capability of MV-CHT-based sensing catalysts with bioactive molecules, which make them as superior drug monitoring devices. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：Both spherical MnO as adsorbent and Ni nanoparticles as catalyzer, with highly exposed contact surface area in the carbon nanofibers, are successfully synthesized via electrospinning technology combined with carbothermal reduction. Compared with typical electrospun carbon nanofiber composites, the as-prepared C@Ni/MnO composite fibers as interlayer enable MnO and Ni to contact fully with polysulfides rather than provide local contact surface. With the sulfur loading of 1.6 mg cm(-2) and the approximately 0.1 g composite fibers as interlayer, the cathode shows initial capacity of 687.36 mAh g(-1) at 0.5C and superior capacity retention of 70%. This simple technical route leads a way to prepare nanoparticles with highly exposed contact surfaces partially embedded in the carbon nanofibers, which can be applied in electrocatalysis. (C) 2022 Published by Elsevier Inc.
查看更多>>摘要：Transition-metal compounds have attracted enormous attention as potential energy storage materials for their high theoretical capacity and energy density. However, the most present transition-metal compounds still suffer from severe capacity decay and limited rate capability due to the lack of robust architectures. Herein, a general metal-organic framework-derived route is reported to fabricate hierarchical carbon-encapsulated yolk-shell nickelic spheres as anode materials for sodium-ion batteries. The nickelic metal-organic framework (Ni-MOF) precursors can be in situ converted into hierarchical carbonencapsulated Ni2P (Ni2P/C), NiS2 (NiS2/C) and NiSe2 (NiSe2/C) by phosphorization, sulfuration, and selenation reaction, respectively, and maintain their yolk-shell sphere-like morphology. The as-synthesized Ni2P/C sample can deliver much lower polarization and discharge platform, smaller voltage gap, and faster kinetics in comparison with that of the other two counterparts, and thus achieve higher initial specific capacity (3222.1/1979.3 mAh g1) and reversible capacity of 765.4 mAh g-1 after 110 cycles. This work should provide new insights into the phase and structure engineering of carbon-encapsulated transitionmetal compound electrodes via MOFs template for advanced battery systems. (c) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：Heteroatom-doped three-dimensional (3D) porous carbons possess great potential as promising electrodes for high-performance supercapacitors. Inspired by the inherent features of intumescent flame retardants (IFRs) with universal availability, rich heteroatoms and easy thermal-carbonization to form porous carbons, herein we proposed a self-assembling and template self-activation strategy to produce N/P dual-doped 3D porous carbons by nano-CaCO3 template-assistant carbonization of IFRs. The IFRs-derived carbon exhibited large specific surface area, well-balanced hierarchical porosity, high N/P contents and interconnected 3D skeleton. Benefitting from these predominant characteristics on structure and composition, the assembled supercapacitive electrodes exhibited outstanding electrochemical performances. In three-electrode 6 M KOH system, it delivered high specific capacitances of 407 F g(-1) at 0.5 A g(-1), and good rate capability of 61.2% capacitance retention at 20 A g(-1). In two-electrode organic EMIMBF4/PC system, its displayed high energy density of 62.8 Wh kg(-1) at a power density of 748.4 W kg(-1), meanwhile it had excellent cycling stability with 84.7% capacitance retention after 10,000 cycles. To our best knowledge, it is the first example to synthesize porous carbon from IFRs precursor. Thus, the current work paved a novel and low-cost way for the production of high-valued carbon material, and expanded its application for high-performance energy storage devices. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：Catalytic oxidation plays important roles in energy conversion and environment protection. Boron-doped crystalline carbocatalyst has been demonstrated effective; however, the application potential of boron-doped amorphous carbocatalyst remains to be explored. For amorphous carbon material, finite-sized carbon clusters are the basic structural units, which exhibit unique activity due to edge and size effect. Herein, using sulfur dioxide (SO2) and carbon monoxide (CO) oxidation as probe thermal-catalysis reactions, we found the distribution and reactivity of active sites in boron-doped carbon clusters are simultaneously determined by dopants and edges. According to comparisons of oxygen (O-2) chemisorption energy at different sites of symmetric and non-symmetric carbon cluster, the most active site is found to be the edge carbon atom with high electron donation ability, which can be accurately identified by electrophilic Fukui function. More importantly, the reactivity of boron-doped cluster is simultaneously influenced by doping configuration and the type of edge, based on which -O-B-O- configuration embedded into K-region edge (isolated carbon-carbon double bonds that do not belong to Clar sextet) is predicted to exhibit the highest reactivity among various boron doping configurations. This work clarifies unique activity origin of heteroatom-doped amorphous carbon materials, providing new insights into designing high-performance carbocatalysts. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：Nitrogen doping could improve the catalytic performance of carbon materials, in which the nitrogen configuration could be used as active sites for peroxymonosulfate (PMS) activation. Herein, this paper studied how to turn waste to "treasure" by agriculture waste pomelo peel to prepare nitrogen-doped biochar and successfully applied it to advanced oxidation field. The effects of the sodium bicarbonate (NaHCO3), melamine, and pyrolysis temperature on the catalytic activity of biochar for the removal of sulfamethoxazole (SMX) were investigated. The optimized nitrogen-doped biochar (C-N-M 1:3:4) possessed high specific surface area (SSA, 738 m(2)/g) and high level of nitrogen doping (nitrogen content 13.54 at%). Accordingly, it exhibited great catalytic performance for PMS activation to remove SMX antibiotic, and 95% of SMX was removed within 30 min. High catalytic activity of C-N-M 1:3:4 was attributed to rich defects, carbonyl group, high content of graphitic N and pyrrolic N, and large SSA, in which non-radical oxidation process based on singlet oxygen (O-1(2)) and electron transfer contributed to the SMX degradation. The prepared nitrogen-doped biochar possessed high stability and reusability and the removal efficiency of SMX still reached 80% after four cycles. Additionally, the phytotoxicity assay indicated that the toxicity of degradation intermediates was obviously decreased in the PMS/C-N-M 1:3:4 system. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：The efficient enrichment and reutilization of phosphate from natural water still remains a daunting challenge to satisfy the increasingly stringent phosphate discharge criteria. In response to this problem, the presented study successfully synthesizes a series of magnetic zeolitic imidazolate framework-8@engineering nanomaterials (ZIF8@ENMs) via a two-step hydrothermal and coprecipitation method by facilely growing ZIF8 and/or Fe3O4 on various functional ENMs. Structure morphology, chemical composition and hysteresis curve characterizations demonstrate the successful formation of magnetic Fe3O4-ZIF8@ENM. Amongst the prepared magnetic ZIF8@ENMs hybrids, the Fe3O4-ZIF8@ENMs possessing massive hydroxyl groups is demonstrated to harvest the maximum adsorption capacity of 441.7 mg g(-1) under neutral condition. Such-acquired adsorption capacity evidently surpass state-of-the-art adsorbents. Systematic assessment of the chemical condition effects on phosphate removal, revealing its conspicuous merits of robust pH independence (94.63-98.20%), high selectivity pinpointing phosphate within complex cations, ease-of-separation and satisfactory recycle. The outstanding performance of magnetic ZIF8@ENMs are mainly derived from the formed strong Zn-O-P, Fe-O-P and electrostatic interactions between phosphate and adsorbents. Along this line, designing magnetic MOFs-based hybrids towards phosphate are anticipated to be promising avenues for advanced treatment of phosphate-like contaminants and efficient recycle in practical applications. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：The distinctive pomegranate-like Nb2O5/Carbon@N-doped carbon (Nb2O5/C@NC) composites are fabricated using hydrothermal method integrated with nitrogen doped carbon coating procedure. For the SIBs anode, the Nb2O5/C@NC composites present superior rate character and sustainable capacity (117 mAh g(-1) upon 1000 cycles at 5 A g(-1)). The in-situ X-ray diffraction (XRD) is utilized to research its sodium storage mechanism. Furthermore, for PIB5, the Nb2O5/C@NC composites present sustainable capacity (81 mAh g(-1) upon 1000 cycles at 1 A g(-1)). The outstanding performance of Nb2O5/C@NC composites is ascribed to its unique architecture, in which Nb2O5 nanocrystals embedded in porous carbon can restrain agglomeration of Nb2O5 nanocrystals, enhance electron/ion diffusion kinetics, and ensure electrolyte accessibility, and moreover, NC shell layer can provide effective active sites and further increase ions/electrons transfer. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：Hydrogel-based wearable sensors have gained great interest on account of their huge application in human-machine interfaces, electronic skin, and healthcare monitoring. However, there are still challenges in designing hydrogel-based sensors with high stability in a wide temperature range, superior adhesion, and excellent sensitivity. Herein, sensors based on oxidized sodium alginate (OSA)/polyacrylamide (PAm)/polydopamine-Ti3C2Tx (PMXene) /glycerol/water (Gly/H2O) organohydrogels were designed. The organohydrogels exhibited excellent mechanical properties (elongation at break of 1037%, tensile strength of 0.17 MPa), predominant self-healing ability (self-healing efficiency of 91%), as well as high sensing stability in a wide temperature range (from -20 to 60 degrees C). The introduction of PDA (polydopamine) and viscous glycerin (Gly) provide organohydrogels with superior adhesion. Organohydrogels sensors demonstrated high sensitivity (Gauge Factor, GF = 2.2) due to the combination of ionic and electron conduction. Sensors could stably detect human movement under different strain levels at high and low temperatures, providing a new solution for wearable sensors in extreme conditions. (C) 2022 Elsevier Inc. All rights reserved.
查看更多>>摘要：The hydrothermally prepared two-dimensional copper selenide nanosheets (2D CuSe NSs) have been employed for the first time to degrade rhodamine B (RhB) in the presence of hydrogen peroxide (H2O2) under ultraviolet to near-infrared (NIR) light irradiation and dark condition. The experimental measurements demonstrate that 99.7% RhB is degraded under NIR light irradiation for 120 min. Moreover, the experimental tests clearly demonstrate that the 2D CuSe NSs display excellent ability to degrade RhB under dark condition. The different degradation mechanisms under the light irradiation and dark condition have been revealed by the experimental tests through the investigation of H(2)O(2 )role and the evaluation of hydroxyl radicals (center dot OH) and H2O2 concentration during the degradation reaction. Under light irradiation, the H(2)O(2 )traps the photogenerated electrons of the CuSe to generate center dot OH and hydroxide ion (OH ), and the holes react with OH to produce center dot OH, making RhB to be degraded efficiently. Under dark conduction, the 2D CuSe NSs react with H(2)O(2 )to exhibit Fenton-like process to degrade RhB with a degradation rate of 90.0% within 120 min. This work opens a pathway for developing nanostructures with full-solar-responsive and strong near-infrared photocatalytic activity as well as Fenton-like reaction to efficiently degrade pollutants under light irradiation and dark condition. (C) 2022 Elsevier Inc. All rights reserved.
NSTL
Elsevier