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Deposition of Cu nanoclusters produced by compact gas aggregation nanocluster source without size filtration is investigated. The main emphasis is given to the determination of influence of operating conditions (pressure in the ag...
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Deposition of Cu nanoclusters produced by compact gas aggregation nanocluster source without size filtration is investigated. The main emphasis is given to the determination of influence of operating conditions (pressure in the aggregation and deposition chambers, magnetron current) on deposition rate of Cu nanoclusters as well as on the evaluation of their size distribution and chemical structure. Subsequently, possibility to employ this nanocluster source for fabrication of Cu nanodusters/plasma polymer multilayer nanocomposites was tested. It is shown that by step-by-step deposition of layers of Cu nanoclusters and plasma polymer it is possible to control not only amount of Cu nanoclusters incorporated into plasma polymer, but also roughness, wettability and optical properties of resulting coatings without affecting their surface chemical composition.
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In this work, Cu nanoclusters (Cu NCs) with strong aggregation-induced electrochemiluminescence (AIECL) as emitters were used to construct an ECL biosensor for ultrasensitive detection of microRNA-141 (miR-141). Impressively, the ...
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In this work, Cu nanoclusters (Cu NCs) with strong aggregation-induced electrochemiluminescence (AIECL) as emitters were used to construct an ECL biosensor for ultrasensitive detection of microRNA-141 (miR-141). Impressively, the ECL signals enhanced with the increased content of Cu(I) in the aggregative Cu NCs. When the ratio of Cu(I)/Cu(0) in aggregative Cu NCs was 3.2, Cu NCs aggregates showed the highest ECL intensity, in which Cu(I) could enhance the cuprophilic Cu(I)center dot center dot center dot Cu(I) interaction to form rod-shaped aggregates for restricting nonradiative transitions to obviously improve the ECL response. As a result, the ECL intensity of the aggregative Cu NCs was 3.5 times higher than that of the monodispersed Cu NCs. With the aid of the cascade strand displacement amplification (SDA) strategy, an outstanding ECL biosensor was developed to achieve the ultrasensitive detection of miR-141, whose linear range varied from 10 aM to 1 nM with a detection limit of 1.2 aM. This approach opened an avenue to prepare non-noble metal nanomaterials as robust ECL emitters and provided a new idea for detection of biomolecules for diagnosis of disease.
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Metal nanoclusters exhibit strong fluorescence emission, providing immense potential for developments in biological labeling and imaging. Copper nanoclusters in particular, due to their unique optical properties such as molecular-...
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Metal nanoclusters exhibit strong fluorescence emission, providing immense potential for developments in biological labeling and imaging. Copper nanoclusters in particular, due to their unique optical properties such as molecular-like absorption and strong luminescence, represent a novel fluorescent nanomaterial for sensing and bioimaging applications. This review describes research progress on Cu nanoclusters in recent years, investigating the synthesis techniques, their properties, and their promising applications. A concluding summary provides an outlook on the future research challenges for Cu nanoclusters and their corresponding synthesis techniques.
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In this study, we present solid state processes for the fabrication of copper nanoclusters (NCs) and hierarchical supraparticles (SPs). To achieve this, copper salt and thiols are mixed and are then grinded for 10–15 min, and the...
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In this study, we present solid state processes for the fabrication of copper nanoclusters (NCs) and hierarchical supraparticles (SPs). To achieve this, copper salt and thiols are mixed and are then grinded for 10–15 min, and the nano-products are thereby obtained. Interestingly, it was found in this study that the formation of the NCs or SPs is completely dependent on the grinding methods that are used: with mechanical grinding, the products are several nanometer-sized NCs, whereas manual grinding in an agate mortar can obtain Cu SPs with diameters as low as 10 nm all the way up to 200 nm. The photoluminescence emission wavelength of the nano-products is located at ~680 nm. The Stokes shift of the obtained nanomaterials is more than 300 nm. The emission quantum yields of the Cu NCs and SPs are as high as 47.5% and 63%, respectively. Due to their facile fabrication processes and their favorable optical properties, the two as-prepared types of copper nano-materials exhibit great potential for bio-imaging and bio-sensing applications.
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Transition metal oxides (TMOs) have been commonly considered as promising anode materials for next generation lithium ion battery (LIB) due to their high specific capacity, environmental friendliness, low cost and natural abundanc...
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Transition metal oxides (TMOs) have been commonly considered as promising anode materials for next generation lithium ion battery (LIB) due to their high specific capacity, environmental friendliness, low cost and natural abundance. Herein, we demonstrate that hematite (alpha-Fe2O3) microspheres of different morphologies can be easily modulated with the assistance of small amount of Cu ions during solvothermal synthesis. Through combined spectroscopic, structural and compositional analysis, the root of hematite morphology change and incurred electrochemical property enhancement were investigated in detail. It was found that Cu ions play a great role at different stage of the synthesis, namely guiding particle growth at its low concentration, whereas being reduced to Cu nanoclusters at its high concentration, executively enhancing overall electrochemical performance of the anode. To explain the particle morphology change induced by Cu ion concentration, a particle growth mechanism involving the interaction of multiple reactions was proposed and studied accordingly.
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Multistimuli-responsive fluorescent gelsbased small molecular gelator by supramolecular assembly, possessing excellent dynamic and reversible characteristic, have caused much concern. In this article, aggregation-induced emission-...
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Multistimuli-responsive fluorescent gelsbased small molecular gelator by supramolecular assembly, possessing excellent dynamic and reversible characteristic, have caused much concern. In this article, aggregation-induced emission-active fluorescence gels (AIE-gels) with chirality were developed by combining Cu nanoclusters (CuNCs) and natural amino acids, L-tryptophan (L-Trp) or D-Tryptophan (D-Trp). In DMSO/H2O mixed solvents, CuNCs can self-assemble to form intertwined fibersbased nanoparticles with numerous pores by introducing Zn2+. Fibers as second networks of heteronetwork structures are characterized with the participation of L-Trp or D-Trp for cross-linking to reinforce mechanical strength and chiral regulation of gel networks. Aggregation-induced emission enhancement (AIEE) of CuNCs endows the gels with excellent fluorescent properties by introducing solvents and gelation process. The fluorescent gels exhibit sufficient fluorescence intensity (FI) at -20 degrees C to -80 degrees C and possess sensitive responsibility including gel-sol transition and fluorescence behavior for stimuli of mechanical force, heating, pH, H2O2, and ethylene diamine tetraacetic acid (EDTA).
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Multistimuli-responsive fluorescent gelsbased small molecular gelator by supramolecular assembly, possessing excellent dynamic and reversible characteristic, have caused much concern. In this article, aggregation-induced emission-...
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Multistimuli-responsive fluorescent gelsbased small molecular gelator by supramolecular assembly, possessing excellent dynamic and reversible characteristic, have caused much concern. In this article, aggregation-induced emission-active fluorescence gels (AIE-gels) with chirality were developed by combining Cu nanoclusters (CuNCs) and natural amino acids, L-tryptophan (L-Trp) or D-Tryptophan (D-Trp). In DMSO/H2O mixed solvents, CuNCs can self-assemble to form intertwined fibersbased nanoparticles with numerous pores by introducing Zn2+. Fibers as second networks of heteronetwork structures are characterized with the participation of L-Trp or D-Trp for cross-linking to reinforce mechanical strength and chiral regulation of gel networks. Aggregation-induced emission enhancement (AIEE) of CuNCs endows the gels with excellent fluorescent properties by introducing solvents and gelation process. The fluorescent gels exhibit sufficient fluorescence intensity (FI) at -20 degrees C to -80 degrees C and possess sensitive responsibility including gel-sol transition and fluorescence behavior for stimuli of mechanical force, heating, pH, H2O2, and ethylene diamine tetraacetic acid (EDTA).
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Abstract Selective detection of Al3+ is of great significance both for the benefit of human health and environmental safety considerations. In this work, a sensitive and selective fluorescence assay for Al3+ was proposed based on ...
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Abstract Selective detection of Al3+ is of great significance both for the benefit of human health and environmental safety considerations. In this work, a sensitive and selective fluorescence assay for Al3+ was proposed based on the green‐emissive Cu nanoclusters (Cu NCs). Different from the commonly reported works, the green emissive Cu NCs showed dual emission bands at 450 and 510?nm, attributed to the reaction product between polyvinyl pyrrolidone and ascorbic acid and the Cu core, respectively. Al3+ could induce the aggregation of Cu NCs by forming covalent bonds, which results in the enhancement of photoluminescence intensity. This enhancement phenomenon is rather selective to Al3+, which endows the detection in real samples. These results provide new insights for the fluorescence mechanisms of metal NCs, which also provided a functional luminescent material for various applications, such as chemical sensing, bioimaging and photoelectric devices.
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ZnS and their Cu-doped nanoclusters (NCs) were synthesized successfully using the wet chemical route with different Cu content. The crystalline structure was investigated using x-ray powder diffraction which assured the single-pha...
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ZnS and their Cu-doped nanoclusters (NCs) were synthesized successfully using the wet chemical route with different Cu content. The crystalline structure was investigated using x-ray powder diffraction which assured the single-phase formation in cubic symmetry. High-resolution transmission electron microscope indicated the microstructure of NCs with a size ranging from 2-4 nm. A butterfly hysteresis (M-H) loop was observed at room temperature with large values of coercivity for the Cu content of x = 0.05. Photoluminescence emission spectra were recorded from 500-615 nm for pure and Cu-doped ZnS NCs at a 350 nm excitation wavelength. The sample exhibited green fluorescence bands peaking at 535, 544, 552.5, 558.2, and 560.6 nm, which confirmed the characteristic feature of Zn2+ as luminescent centers in the lattice. The additional yellow and orange emissions are due to defect levels or/and impurity centers. The dielectric constant as well as the conductivity values increased with increasing Cu content.
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The evolution of nanoclusters in sequentially ion-implanted Cu/Ag into silica glasses has been studied. The doses for implantation (x 10(16) ions/cm(2)) were 5Cu/5Ag, 5Cu/10Ag and 5Cu/15Ag, respectively. The microstructural proper...
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The evolution of nanoclusters in sequentially ion-implanted Cu/Ag into silica glasses has been studied. The doses for implantation (x 10(16) ions/cm(2)) were 5Cu/5Ag, 5Cu/10Ag and 5Cu/15Ag, respectively. The microstructural properties of the nanoclusters are characterized by optical absorption spectra and transmission electron microscopy (TEM). Fast nonlinear optical refraction and nonlinear optical absorption coefficients were measured at 1064 nm of wavelength using Z-scan technique. Results in this project indicate that different optical nonlinearities could be selectively obtained at the near-infrared region of 1064 nm of wavelength by changing the metal ingredient percentage in silica. (c) 2007 Elsevier B.V. All rights reserved.
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