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Transition metal dichalcogenides MS2 (M = Mo, W, Nb, Ta) have the lamellar structures similar to graphite. They are often used as solid lubricants in high/low temperature, high load, vacuum, in which oil lubrication is failed. We have synthesized WS2 nanotubes with decomposition method using Al2O3 template. Moreover, chemical vapor transportation reaction is used to produce NbS2 nanotubes in evacuated...
Functionalized quantum dots have been successfully attached to multi-walled carbon nanotubes over carbodiimide-assisted coupling. Characterization in a transmission electron microscope shows the quantum dots are attached mainly at the opened tips and defect sites on the side-walls of nanotubes, suggesting the covalent nature of the bonding and high selectivity to chemically reactive sites. Due to...
Carbon nanofibers (CNFs) are synthesized at 450-650degC by a catalytic CVD method using nickel powders reduced from nickel carbonate as catalyst without other supporting materials, and acetylene as carbon source. It is found that the nickel powders present a considerable catalytic efficiency in the growth of the CNFs at the temperature between 500-550degC. TEM observation shows that a large portion...
Bamboo-shaped multiwall carbon nanotubes (BS-MWCNTs) activated by KOH with different KOH/CNT mass ratio are applied as electrodes for supercapacitors. The electrochemical capacitance of activated bamboo-shaped multiwall carbon nanotubes (ABS-MWCNTs) with KOH/CNT mass ratio 3:1 and 7:1 is 1.5 and 3 times that of the normal BS-MWCNTs, respectively. The activated materials still possess nanotubular morphology...
The SrAl2O4: Eu2+, Dy3+ phosphor nanoscale powders with high brightness were prepared by a nano-coating process. The resulted SrCO3@ Al2O3 core-shell precursors were characterized by transmission electron microscope (TEM), which indicates that the precursor particles have narrow size distribution. The structure and optical properties of the phosphor powders were investigated systematically by means...
A novel room temperature synthesis of carbon nanotubes (CNTs) by liquid phase deposition of methanol is firstly reported. Nanotube samples were characterized with field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Raman spectroscopy. FESEM micrographs revealed that nanotubes with diameter in the range of 20-200 nm were grown at room temperature. HR-TEM...
Magnetite (Fe3O4) nanoparticles uniformly loaded on multi-walled carbon nanotubes (MWCNTs) were synthesized by a wet chemistry method, and then carbon coated Fe3C nanoparticles supported by MWCNTs were prepared by heat-treatments subsequently in nitrogen at 600 degC and in acetylene atmosphere at 500 degC. The as-prepared nanoparticles were all single crystals with a size distribution ranging from...
In this research, by adding methyl alcohol/water solution with certain concentration into sol to hydrolysis directly and sintering the fresh gel directly, lead titanate ceramics doped with calcium are prepared by using calcium acetate as doper to prohibit the disadvantages contained in conventional sol-gel method, such as low hydrolytic rate, high sintering temperature, long preparation period. The...
In order to understand the formation mechanism of nano- materials during the arc discharge in liquid, serial experiments were conducted on synthesis of nano-materials by arc discharge both in water and in liquid nitrogen. Previous research showed that the stability of arc discharge affected the nano-products significantly. In this paper, the cross magnetic field (CMF) was introduced to disturb the...
As2S3 is playing an important role in the treatment and research for human cancer, but many limitations exist because of its form. We studied preparation method of As2S3 nanoparticles, a completely new form of medicine containing arsenic and explored their antitumor effect. As2S3 nanoparticles were prepared chemically and characterized by Transmission electron microscope and energy dispersive spectrometry...
High yields of multi-walled carbon nanotubes are synthesized by chemical vapor deposition of acetylene on palladium nanoparticles supported on porous SiO2. HRTEM results reveal that the carbon nanotubes have novel conical inner structure. By changing the content of palladium in the catalyst, we obtained palladium nanoparticles with different diameter distribution. It was found that the apex angles...
Nanojet means that the liquid is forced to pass through the nozzle with the nanosize diameter, we report here that nanojet was formed for the first time in lab by heating the PbO coated Pb clusters. In this experiment, the coated clusters are heated to more than 200 C and it was found that the inner Pb core melted and ran out from the cracked outer shell with a 200-nm-long(as long) trail. The in situ...
Determination of the helicity of carbon nanotubes (CNTs) is useful for CNTs in nanoelectronic device applications. Using electron diffraction to measure chiral angle with a high precision is reviewed, and helix-shaped carbon nanostructures are introduced and characterized by transmission electron microscopy. The possible formation mechanism of helix-shaped CNTs is also referred in the paper
Nd3+ doped PbZr0.52Ti0.48O3 (PNZT) nanopowders were prepared by sol-gel methods in ethylene glycol system. Neodymium nitrate was used as Nd3+ source. The reaction mechanisms of nanopowder preparing process from the sol were discussed through using FTIR, XRD, TG-DTA, and it was proved that the heating temperature of PNZT was 50degC-100degC higher than PZT. PNZT lattice structure was characterized...
The objective of this paper is to study the therapeutic effect of nanosized As2O3/Fe3O4 complex (Fe3O4 magnetic nanoparticles containing As2O3) combined with magnetic fluid hyperthermia (MFH) on human cervical cancer Hela cells in vitro and xenograft cervical cancer in nude mice. The growth and apoptosis of Hela cells treated with nanosized As2O3/Fe3O4 complex combined with MFH was examined by MTT,...
Fe3O4 single crystal nanoparticles were prepared in zero field and in a magnetic field. Fe3O4 with well crystallinity is achieved in a magnetic field. X-ray diffraction, transmission electron microscopy, vibrating sample magnetometer and Mossbauer spectrum analysis have confirmed that the magnetic field results in increasing crystallinity, such as decrease surface spin disorder and cation vacancies...
Structural instability of single wall carbon nanotube under electron beam irradiation was investigated by our developed in-situ transmission electron microscopy observation technique. It was observed that the nanotube shrunk and necked in diameter gradually and the curved nanotube shrunk faster in axis direction than straight one with increasing of electron dose during the irradiation. Such athermally...
Field emission properties of carbon nanotubes (CNTs) filled with single crystalline Cu nanoneedles at their tips have been investigated in situ with an STM-TEM holder. The CNTs are synthesized using an alkali doped Cu catalyst by a thermal chemical vapor deposition method. Experiments show that CNTs filled with Cu have a much lower turn-on voltage (generally lower than 75V) than those without Cu (>...
Spindle-type α-Fe2O3 nanoparticles have been synthesized via a hydrothermal method, using Fe(NO3)3, NH4Cl and ethylene glycol as starting precursors. The resultant products were characterized by means of Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer...
Nano-sized ZnO crystals with catalytic, electrical, optoelectronic, and photochemical properties have been considered as an important candidate in both fundamental research and practical studies. However, controllable synthesis of ZnO in morphology and size with a simple method under mild conditions still represents a challenge. We proved that ZnO nanostructures, including particles and nanorods,...
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