Journal of nanoscience and nanotechnology最新文献

Occupational exposure to indium oxide and indium containing particles has been associated with the development of severe lung diseases called "indium lung." According to the survey of occupational hygiene, indium oxide nanoparticles have been identified in the workplaces and the lungs of workers. To date, the potential mechanism of the pneumotoxicity has been poorly understood and no effective therapies are available against "indium lung." Our present study reported that the exposure of indium oxide nanoparticles damaged lung epithelial cells and alveolar macrophages and induced pulmonary alveolar proteinosis and inflammation in rats. In the 8-week post-exposure period, the indium oxide nanoparticles still mostly accumulated in the lungs and then persistently release indium ions in two months after exposure. In vitro, the epithelial cells show the greater potential for release of indium ions from indium oxide nanoparticles compared with the macrophages. EDTA-2Na, a metal chelating agent expected to remove the indium ions, was found to significantly reduced the cytotoxicity of indium oxide nanoparticles. Herein, the pneumotoxicity may be attributed to the slow and incremental release of indium ions from indium oxide nanoparticles primary dissolved by epithelial cells and macrophages, at least partially. The study may provide some insights to the pathogenicity mechanisms of "indium lung" and some clues against the health hazards of occupational inhaled indium oxide nanoparticles at the workplaces.

ScPO₄:Eu³⁺, Tb³⁺ phosphors with tuned emission color were prepared through high temperature solid-state reaction. The structure, morphology and photoluminescence properties of the title samples were collected by XRD, SEM and fluorescence spectrophotometer, respectively. Co-doping Eu³⁺ and Tb³⁺ in ScPO₄ does not change the body-centered tetragonal structure of the host. And the morphology remains essentially unchanged except for slight agglomeration. Changing the ratio of Tb³⁺/Eu³⁺, the tuned emission can be achieved, the color could be adjusted from green through yellow to orange-red. The ScPO₄:0.03Tb³⁺, 0.03Eu³⁺ phosphor with high thermal stability as the single matrix phosphor can be suitable for the NUV-pumped white LED. The white LED with a color rendering index of 86.5 and a correlated color temperature of 3470 K has been generated by packaging BAM:Eu²⁺ with ScPO₄:0.03Tb³⁺, 0.03Eu³⁺ on an NUV-InGaN chip.

Innovative nitrogen and boron co-doped carbon dots are hydrothermally produced using fructose, urea, and boric acid as precursors. The synthesized carbon dots possess a uniform morphology, and exhibit excellent fluorescence stability, tunable luminescence property, strong resistance to photobleaching, low-toxicity, and excellent biocompatibility. It is also found more dopant urea is conducive to the formation of the carbon dots with more B-N bonds, and shorter wavelength of fluorescence emission. Meanwhile, the synthesized carbon dots are well utilized as a photoluminescent probe for facile Hg²⁺ determination and fluorescent imaging reagent in cells.

In this work, we have synthesized a nanocomposite ZnS/CdS/Pt/TiO₂ nanotube arrays (denoted ZCP-NTAs). Firstly, TiO₂ nanotube array (NTAs) material was fabricated by the anodic method of a titanium plate in an electrolyte solution containing 0.35 M NaHSO₄ and 0.24 M NaF and incubated in the air at 500 ºC for 2 hours. After that, pulsed electrodeposition technology was used to decorate platinum nanoparticles (denoted as Pt NPs) onto the surface of TiO₂ nanotubes to form P-NTAs photoelectrodes. Then, the SILAR method is used to deposition CdS quantum dots (symbolized as CdS QDs) on the surface of P-NTAs to form CP-NTAs material. Finally, by the SILAR method, a ZnS passive layer that protects against optical corrosion and inhibits recombination of e^-/h⁺ pairs was coated onto the CP-NTAs to form ZCP-NTAs material. As-prepared ZCP-NTAs photocatalytic material has good absorbability of light in the visible region with light absorption wavelength up to 608 nm, photon conversion efficiency up to 5.32% under light intensity AM1.5G, and decomposition efficiency of 10 mg L^-1 methyl orange (MO) in 120 minutes reached 91.50%. This material promises to bring high application ability in the photocatalytic field applied for environmental treatment and other applications.

In this work, we demonstrate controlled introduction of O-functional groups on commercial carbon nanotube fibers (CNTFs) with different nanotube morphologies obtained by dry- and wet-spinning by treatment with gaseous ozone (O₃(g)). Our test samples were (1) wet-spun fibers of smalldiameter (1-2 nm) singlewall (SW)-CNTs and (2) dry-spun fibers containing large-diameter (20 nm) multiwall (MW)-CNTs. Our results indicate that SW-CNTFs undergo oxygenation to a higher extent than MW-CNTFs due to the higher reactivity of SW-CNTs with a larger curvature strain. Oxygenation resulting from O₃ exposure was evidenced as increase in surface O atomic% (at% by X-ray photoelectron spectroscopy, XPS) and as reductions in G/D (by Raman spectroscopy) as well as electrical conductivities due to changes in nanotube graphitic structure. By XPS, we identified the emergence of various types of O-functionalities on the fiber surfaces. After long duration O3 exposure (>300 s for SW-CNTFs and >600 s for MW-CNTFs), both sp² C═O (carbonyl) and sp³ C-O moieties (ether/hydroxy) were observed on fiber surfaces. Whereas, only sp³ C-O (ether/hydroxy) components were observed after shorter exposure times. O₃ treatment led to only changes in surface chemistry, while the fiber morphology, microstructure and dimensions remained unaltered. We believe the surface chemistry controllability demonstrated here on commercial fibers spun by different methods containing nanotubes of different structures is of significance in aiding the practical application development of CNTFs.

We evaluated the effect of dilution on both the size and packing density of aggregates prepared from a fatty acid (oleic acid, OA)/detergent (3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxypropane sulfonate (CHAPSO)) bicelle as a parent for functional membrane materials. The sizes of the aggregates formed at different molar ratios, X_OA(= [OA]/([OA]+[CHAPSO])), of 0.3 and 0.7 and their parent bicelles were measured by dynamic light scattering and transmission electron microscopy; their packing density was evaluated by deconvolution of the fluorescence spectrum, where Laurdan molecules were used as a probe. The experimental results showed that the bicelles formed aggregates upon dilution because of the hydration of CHAPSO. The packing density of the nano-ordered aggregate formed at X_OA = 0.3 was much greater than that of the aggregate formed at X_OA = 0.7, implying the formation of an ordered aggregate under the condition of X_OA = 0.3.

Cadmium sulfide (CdS), an II-VI group semiconductor material, is one of the most investigated semiconductors in thin film form. In this work, we synthesized CdS thin films with improved film morphology in the presence of ethylene diamine (EA) as the complexing agent by chemical bath deposition (CD) at lower pH. Detailed characterization reveals the presence of cubic phase CdS with a band gap of 2.39 eV with the resultant morphology significantly influenced by the composition of the growth solution. The resultant CdS films finds prospective application as a humidity sensor with a high sensor response of 2.61 corresponding to 80% relative humidity.

Using first principles calculations, we have presented a short study on modulation of band structures and electronic properties of zigzag blue phosphorene (ZbPNR) and arsenene nanoribbons (ZANR) by etching the edges of NRs. We have taken the width of both NRs as N = 8 and corrugated the edges in a cosine-like manner. Optimizing every structure and further investigating their stabilities, it was seen that both the etched NRs are energetically feasible. From the computed band structures, the band gaps were seen to be increased for both the NRs on increasing number of etched layers and direct gap semiconductor nature was recorded. Highest energy gap observed were 2.26 and 2.41 eV for ZbPNR and ZANR, respectively. On further application of electric field, we observed the very interesting semiconductor-to-metallic property transition which was explained by wave function plots. Being elements of same group, a similar trend of band gaps modulations was observed for both NRs. This fascinating method of electronic property tuning of the studied NRs can be useful in various nanoscale electronic applications.

Nanotechnology has the ability to produce novel nano-sized materials with excellent physical and chemical properties to act against phytopathogenic diseases, essential for revolution of agriculture and food industry. The development of facile, reliable and eco-friendly processes for the synthesis of biologically active nanomaterials is an important aspect of nanotechnology. In the present paper, we attempted to compare sonochemical and co-precipitation method for the synthesis of metal sulfide nanoparticles (MS-NPs) for their structural and antifungal properties against various phytopathogenic fungi of rice. The preparation of nanospheres (NSs) and nano rods (NRs) of CuS, FeS and MnS was monitored by UV-Visible spectroscopy complemented by transmission electron microscope (TEM), scanning electron microscope (SEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and Zeta potential analyser. Sonochemical method resulted in formation of spherical shaped nanoparticles of size (7-120 nm), smaller than those of nanorods (50-200 nm) prepared by co-precipitation produced. It was observed that the metal sulfide nanospheres exhibited a better antifungal potential against D. oryzae, C. lunata and S. oryzae as compared to rod shaped metal sulfide nanoparticles. Smaller size and large surface area of spherical shaped particles opens up an important perspective of the prepared MS-NPs.