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Ali Rafati Rik ter Veen David G. Castner 《Surface and interface analysis : SIA》2013,45(11-12):1737-1741
With the widespread use of engineered nanoparticles for biomedical applications, detailed surface characterization is essential for ensuring reproducibility and the quality/suitability of the surface chemistry to the task at hand. One important surface property to be quantified is the overlayer thickness of self‐assembled monolayer (SAM) functionalized nanoparticles, as this information provides insight into SAM ordering and assembly. We demonstrate the application of high sensitivity low‐energy ion scattering (HS‐LEIS) as a new analytical method for the fast thickness characterization of SAM functionalized gold nanoparticles (AuNPs). HS‐LEIS demonstrates that a complete SAM is formed on 16‐mercaptohexadecanoic acid (C16COOH) functionalized 14 nm AuNPs. HS‐LEIS also experimentally provides SAM thickness values that are in good agreement with previously reported results from simulated electron spectra for surface analysis of X‐ray photoelectron spectroscopy data. These results indicate HS‐LEIS is a valuable surface analytical method for the characterization of SAM functionalized nanomaterials. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Dr. Mahnaz Najafi Dr. Sara Abednatanzi Abbas Yousefi Prof. Mehrorang Ghaedi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):17999-18014
Photocatalysis has been known as one of the promising technologies due to its eco-friendly nature. However, the potential application of many photocatalysts is limited owing to their large bandgaps and inefficient use of the solar spectrum. One strategy to overcome this problem is to combine the advantages of heteroatom-containing supports with active metal centers to accurately adjust the structural parameters. Metal nanoparticles (MNPs) and single atom catalysts (SACs) are excellent candidates due to their distinctive coordination environment which enhances photocatalytic activity. Metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and carbon nitride (g-C3N4) have shown great potential as catalyst support for SACs and MNPs. The numerous combinations of organic linkers with various heteroatoms and metal ions provide unique structural characteristics to achieve advanced materials. This review describes the recent advancement of the modified MOFs, COFs and g-C3N4 with SACs and NPs for enhanced photocatalytic applications with emphasis on environmental remediation. 相似文献
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Red–Green–Blue Trichromophoric Nanoparticles with Dual Fluorescence Resonance Energy Transfer: Highly Sensitive Fluorogenic Response Toward Polyanions 下载免费PDF全文
Jinjia Xu Dr. Atsuro Takai Prof. Dr. Masayuki Takeuchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(37):13014-13018
A red–green–blue (RGB) trichromophoric fluorescent organic nanoparticle exhibiting multi‐colour emission was constructed; the blue‐emitting cationic oligofluorene nanoparticle acted as an energy‐donor scaffold to undergo fluorescence resonance energy transfer (FRET) to a red‐emitting dye embedded in the nanoparticle (interior FRET) and to a green‐emitting dye adsorbed on the surface through electrostatic interactions (exterior FRET). Each FRET event occurs independently and is free from sequential FRET, thus the resultant dual‐FRET system exhibits multi‐colour emission, including white, in aqueous solution and film state. A characteristic white‐emissive nanoparticle showed visible responses upon perturbation of the exterior FRET efficiency by acceptor displacement, leading to highly sensitive responses toward polyanions in a ratiometric manner. Specifically, our system exhibits high sensitivity toward heparin with an extremely low detection limit. 相似文献
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Luminescent silica nanocomposites functionalized with a Eu-complex have been prepared and characterized.The europium complex is composed of 2,2'-bipyridyl(BPy) and 2-(4-bromomethyI)-phenylpropionic acid(BMPPA),which contains highly active benzyl bromide substituents and can covalently bind with poly(4-vinylpyridine)(P4VP)-modified silica nanoparticles(nanoSiO_2P4VP) to form nanoSiO_2P4VPEuBPy composites.Microscopic images revealed that the nanoSiO_2P4VPEuBPy composites easily formed aggregates,due to an inter-particle binding caused by the benzyl bromide among the composites.The as-prepared nanocomposites showed the typical emissions of Eu(III) ions at the wavelengths from 580 nm to 750 nm designated to the ~5D_0→~7F_n transitions.Time-resolved fluorescence decay measurements revealed that the emission lifetime was approximately 0.204 ms and 0.576 ms for the nanoSiO_2EuBPy composites,a little shorter than that in the Eu(BMPPA)_3BPy complex. 相似文献
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Li Qiang Wu 《应用有机金属化学》2013,27(3):148-154
Nano n‐propylsulfonated γ‐Al2O3 is easily prepared by the reaction of nano γ‐Al2O3 with 1,3‐propanesultone. This reagent can be used as an efficient catalyst for the synthesis of spiro [indoline‐3,4‐pyrazolo[3,4‐e][1,4]thiazepine]diones in aqueous media. This new method consistently has the advantages of excellent yields and short reaction times. Further, the catalyst can be reused and recovered several times. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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