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1.
Silver nanorods have been successfully synthesized via a facile route using sodium tripolyphosphate (Na5P3O10) as the capping agent. Silver nitrate and glucose served as the Ag+ source and green reducing agent in aqueous solution, respectively. The products were characterized by X-ray powder diffraction (XRD), UV–visible spectroscopy (UV–vis), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED). The results showed that the obtained silver nanorods are highly crystallized with an average diameter of 30 nm and lengths up to 400 nm. The linear structure of the capping agent and slow reaction rate are considered to be key factors in the control of particle morphology. The possible formation mechanism has been discussed based on the experimental results. 相似文献
2.
Optical and surface morphological properties of triethylamine passivated lead sulphide nanoparticles
M. Navaneethan K.D. Nisha S. Ponnusamy C. Muthamizhchelvan 《Materials Chemistry and Physics》2009,117(2-3):443-447
The triethylamine capped lead sulphide (PbS) nanoparticles were successfully synthesized by simple wet chemical method. The synthesized product has been characterized by powder X-ray diffraction (XRD), UV–vis spectrophotometry, FTIR spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM) and photoluminescence studies. The size of the PbS nanoparticles was determined from AFM, TEM, XRD and from these studies it is found that the size of the particles of the order of 10–15 nm. Significant “blue shift” from bulk material was observed on the PbS nanoparticles using UV–vis and photoluminescence spectrum. 相似文献
3.
A. Sadeghzadeh Attar M. Sasani Ghamsari F. Hajiesmaeilbaigi Sh. Mirdamadi K. Katagiri K. Koumoto 《Journal of Materials Science》2008,43(17):5924-5929
Well-aligned anatase and rutile TiO2 nanorods and nanotubes with a diameter of about 80–130 nm have successfully been fabricated via sol-gel template method.
The prepared samples were characterized by using thermogravimetric (TG) and differential thermal analysis (DTA), X-ray diffraction
(XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy
(EDS). The XRD results indicated that the TiO2 nanorods were crystallized in the anatase and rutile phases, after annealing at 400–800 °C for different periods of time
from 0.2 to 10 h. 相似文献
4.
Claramaría RodríguezGonzlez Pamela VelzquezVillalba Pedro Salas Víctor M. Castao 《IET nanobiotechnology / IET》2016,10(5):301
A green facile method has been successfully used for the synthesis of graphene oxide sheets decorated with silver nanoparticles (rGO/AgNPs), employing graphite oxide as a precursor of graphene oxide (GO), AgNO3 as a precursor of Ag nanoparticles (AgNPs), and geranium (Pelargonium graveolens) extract as reducing agent. Synthesis was accomplished using the weight ratios 1:1 and 1:3 GO/Ag, respectively. The synthesised nanocomposites were characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, UV‐visible spectroscopy, Raman spectroscopy, energy dispersive X‐ray spectroscopy and thermogravimetric analysis. The results show a more uniform and homogeneous distribution of AgNPs on the surface of the GO sheets with the weight ratio 1:1 in comparison with the ratio 1:3. This eco‐friendly method provides a rGO/AgNPs nanocomposite with promising applications, such as surface enhanced Raman scattering, catalysis, biomedical material and antibacterial agent.Inspec keywords: silver, nanoparticles, graphene, nanocomposites, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, ultraviolet spectra, visible spectra, X‐ray chemical analysis, surface enhanced Raman scattering, catalysis, nanofabricationOther keywords: antibacterial agent, biomedical material, catalysis, surface enhanced Raman scattering, rGO‐AgNP nanocomposite, eco‐friendly method, homogeneous distribution, thermogravimetric analysis, energy dispersive X‐ray spectroscopy, Raman spectroscopy, UV‐visible spectroscopy, X‐ray diffraction, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, nanocomposites, reducing agent, geranium, graphene oxide sheets, graphite oxide, silver nanoparticles, green facile method 相似文献
5.
Jiaqing Geng 《Materials Research Bulletin》2009,44(1):146-87
Nitrogen-doped TiO2 nanotubes with enhanced photocatalytic activity were synthesized using titanate nanotubes as raw material by a facile wet chemistry method. The resulting nanotubes were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy, and UV-vis absorption spectroscopy, etc. The photocatalytic activity of nitrogen-doped TiO2 nanotubes was evaluated by the decomposition of methylene blue under artificial solar light. And it was found that nitrogen-doped TiO2 nanotubes exhibited much higher photocatalytic activity than undoped titanate nanotubes. 相似文献
6.
Formation of transition-metal sulfide microspheres or microtubes 总被引:1,自引:0,他引:1
CuxS (x = 1, 2) microtubes, and a series of transition-metal sulfide (CdS, ZnS, NiS, CoS, CuS and Cu2S) compounds microspheres were successfully synthesized through a facile hydrothermal reaction. These compounds have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The optical properties of ZnS and CdS have also been investigated by UV–vis absorption and fluorescence spectroscopy. The possible formation mechanism of these microspheres or microtubes was discussed based on the experimental results. 相似文献
7.
Liang Zhou Jian Deng Yubao Zhao Wanbing Liu Lin An Fei Chen 《Materials Chemistry and Physics》2009,117(2-3):522-527
N–I co-doped TiO2 nanoparticles were prepared by hydrolysis method, using ammonia and iodic acid as the doping sources and Ti(OBu)4 as the titanium source. The prepared catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and ultraviolet–visible diffuse reflection spectroscopy (UV–vis DRS). XRD spectra show that N–I–TiO2 samples calcined at 673 K for 3 h are of anatase structure. XPS analysis of N–I–TiO2samples indicates that some N atoms replace O atoms in TiO2 lattice, and I exist in I7+, I− and I5+ chemical states in the samples. UV–vis DRS results reveal that N–I–TiO2 had significant optical absorption in the region of 400–600 nm. The photocatalytic activity of catalysts was evaluated by monitoring the photocatalytic degradation of methyl orange (MO). Compared with P25 and mono-doped TiO2, N–I–TiO2 powder shows higher photocatalytic activity under both visible-light (λ > 420 nm) and UV–vis light irradiation. Furthermore, N–I–TiO2 also displays higher COD removal rate under UV–vis light irradiation. 相似文献
8.
Tianyou Zhai Zhanjun Gu Ying Ma Wensheng Yang Liyun Zhao Jiannian Yao 《Materials Chemistry and Physics》2006,100(2-3):281-284
Semiconductor ZnS nanotubes arrays were synthesized in the pores of the porous anodic alumina (PAA) membranes by using metal organic chemical vapor deposition (MOCVD) template methods. The morphology and structure of the ZnS nanotubes were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and X-ray diffraction (XRD). It is found that the ZnS nanotubes with diameters in range of 140–250 nm and the length up to tens of microns are polycrystalline. Energy-dispersion spectroscopy (EDS) and X-ray photoelectron spectroscopy analysis (XPS) indicate that the stoichiometric ZnS was formed. A green-blue emission band centered at 510 nm was observed in the photoluminescence spectrum of the ZnS nanotubes. 相似文献
9.
Xiuxia Meng Xiaoyao Tan Bo Meng Naitao Yang Zi-Feng Ma 《Materials Chemistry and Physics》2008,111(2-3):275-278
Yttria-stabilized zirconia (YSZ) nanotubes were synthesized by the sol–gel method using porous anodic alumina oxide (AAO) as the templates. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersion X-ray (EDX) spectrum and selected area electron diffraction (SAED) techniques were used to characterize the morphology and crystalline structure of the prepared YSZ nanotubes. The length and the diameter of the YSZ nanotubes are 50 μm and 200 nm, respectively, which are in good agreement with the dimensions of the template pores, while the wall thickness of the nanotubes depends on the impregnation time. XRD and SAED measurements indicate that the obtained YSZ nanotubes after sintering at 1073 K possess a polycrystalline structure and a cubic crystal phase. Brunauer–Emmett–Teller (BET) measurement shows that the YSZ nanotubes have a surface specific area of around 40.5 m2 g−1 that is higher than that corresponding to the YSZ nanopowders. 相似文献
10.
Xiaodong Wang Hui PanXiaoxiao Xue Junjie QianLaigui Yu Jianjun YangZhijun Zhang 《Materials Chemistry and Physics》2011
Titanate nanotubes/carbon composites(TNT/CCs) were synthesized by allowing carbon-coated TiO2 (CCT) powder to react with a dense aqueous solution of NaOH at 120 °C for a proper period of time. As-prepared CCT and TNT/CCs were characterized by means of transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectrometry. The processes for formation of titanate nanotubes/carbon composites were discussed. It was found that the TiO2 particles in TiO2-carbon composite were enwrapped by a fine layer of carbon with a thickness of about 4 nm. This carbon layer functioned to inhibit the transformation from anatase TiO2 to orthorhombic titanate. As a result, the anatase TiO2 in CCT was incompletely transformed into orthorhombic titanate nanotubes upon 24 h of reaction in the dense and hot NaOH solution. When the carbon layers were gradually peeled off along with the formation of more orthorhombic titanate nanotubes at extended reaction durations (e.g., 72 h), anatase TiO2 particles in CCT were completely transformed into orthorhombic titanate nanotubes, yielding TNT/CCs whose morphology was highly dependent on the reaction time and temperature. 相似文献
11.
Glow discharge plasma technique was firstly applied to treat amorphous Co–B catalyst. Both the amorphous Co–B particles before and after plasma treatment were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption, and CO temperature-programmed desorption (TPD). After plasma treatment, relatively larger uniform spherical Co–B particles with mesopores have been formed and the synergistic effect between Co and B enhanced. Furthermore, the mesopores formed on the surface of Co–B after plasma treatment enabled it with higher specific surface area. During the liquid-phase cinnamaldehyde (CMA) hydrogenation, Co–B after plasma treatment exhibited higher CMA conversion and cinnamyl alcohol (CMO) selectivity. 相似文献
12.
Ag/ZnO nanoparticles can be obtained via photocatalytic reduction of silver nitrate at ZnO nanorods when a solution of AgNO3 and nanorods ZnO suspended in ethyleneglycol is exposed to daylight. The mean size of the deposited sphere like Ag particles
is about 5 nm. However, some of the particles can be as large as 20 nm. The ZnO nanorods were pre-prepared by basic precipitation
from zinc acetate di-hydrate in the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide. They are
about 50–300 nm in length and 10–50 nm in width. Transmission electron microscopy (TEM), energy-dispersive X-ray analysis
(EDS), X-ray powder diffraction (XRD), UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), and photoluminescence
(PL) were used to characterize the resulting Ag/ZnO nanocomposites. 相似文献
13.
《Materials Research Bulletin》2006,41(6):1097-1104
Three approaches, impregnation–reduction, deposition and direct assembly, are used to fabricate gold-modified TiO2 nanotubes. Prepared materials are characterized with powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), UV–visible absorption spectroscopy and BET, etc. The gold-modified TiO2 nanotubes prepared via various procedures exhibit distinct difference in structure. By impregnation–reduction approach, gold-modified TiO2 nanotubes with large gold particles are fabricated. The gold particles are either deposited on or encapsulated in TiO2 nanotubes. However, by using gold hydrophilic colloidal dispersion as gold precursor, gold particles in the modified TiO2 nanotubes are very small. Gold particles only adhere to the outer surface of TiO2 nanotubes after deposition process, whereas adhere to not only the outer but also the inner walls of TiO2 nanotubes after direct assembly process. A possible mechanism is proposed to illustrate the formation of gold-modified nanotubes that are prepared by direct assembly process. 相似文献
14.
Composites of carbon nanotubes with attached carboxylic groups (c-MWCNTs) and water-soluble externally doped sulfonated polyaniline (ED-SPANI) were prepared by solution mixing of c-MWCNT and ED-SPANI aqueous colloids. Fourier-transform infrared spectroscopy, Raman spectroscopy, ultraviolet–visible (UV–Vis) absorption spectroscopy, field-emission scanning and high-resolution transmission electron microscopy were used to characterize their structure and morphology. Raman and UV–Vis spectra revealed the presence of electrostatic interaction between the C–N+ species of the ED-SPANI and the COO− species of the c-MWCNTs. The addition of c-MWCNT to ED-SPANI can improve its thermal stability. The conductivity of 3 wt.% ED-SPANI/c-MWCNT composites at room temperature is sixteen times higher than that of ED-SPANI. These results demonstrate that the addition of a small number of c-MWCNTs to an ED-SPANI matrix can form a conducting network in well dispersed composites, thus increasing their electrical conductivity. 相似文献
15.
Dana L. Morgan Gerry Triani Mark G. Blackford N. A. Raftery Ray L. Frost Eric R. Waclawik 《Journal of Materials Science》2011,46(2):548-557
In this study, the mechanism of precursor dissolution and the influence of kinetics of dissolution on titanate nanotube formation
were investigated. This comparative study explored the dissolution kinetics for the case of commercial titania powders, one
composed of predominantly anatase (>95%) and the other rutile phase (>93%). These nanoparticle precursors were hydrothermally
reacted in 9 mol L−1 NaOH at 160 °C over a range of reaction times of between 2 and 32 h. The high surface area nanotube-form product was confirmed
using X-ray diffraction, FT-Raman spectroscopy, and transmission electron microscopy. The concentration of nanotubes produced
from the different precursors was established using Rietveld analysis with internal and external corundum standardization
to calibrate the absolute concentrations of the samples. Interpretation of the dissolution process of the precursor materials
indicated that the dissolution of anatase proceeds via a zero-order kinetic process, whereas rutile dissolution is through
a second-order process. The TiO2 nanostructure formation process and mechanism of TiO2 precursor dissolution was confirmed by non-invasive dynamic light scattering measurements. Significant observations are that
nanotube formation occurred over a broad range of hydrothermal treatment conditions and was strongly influenced by the order
of precursor dissolution. 相似文献
16.
Nanostructured titanates with different morphologies such as nanoflakes, nanotubes, and nanofibers have been selectively synthesized
by a simple solvothermal treatment of commercial anatase TiO2 using the mixed water–ethanol cosolvent at low alkaline concentration. The effects of solvothermal temperature, volume ratio
of H2O to C2H5OH, amount of NaOH and solvents on the formation of titanate nanostructures have been systematically studied through X-ray
diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). At
low concentration of NaOH solution (the actual concentration of OH− in the solution is only 0.58 M), different titanate nanostructures are achieved by simply changing the volume ratio of H2O to C2H5OH at 180 °C and titanate nanotubes can be synthesized between 100 and 180 °C. A probable formation mechanism is proposed
based on XRD, SEM and TEM analysis. The influence of cosolvent on the transformation from anatase TiO2 to titanate is also investigated. 相似文献
17.
Nickel nanoparticles coated with zinc sulphide can form complex spherical with a core–shell structure. This coating process was based on mercaptoacetic acid (HSCH2COOH) as a primer to render the nickel surface vitreophilic, thus it renders nickel surface compatible with ZnS. The morphology, structure, chemical composition, optical properties and magnetic properties of the product were investigated by using various techniques, including transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), photoluminescence (PL) spectroscope and vibrating sample magnetometer (VSM). It was found that the Ni/ZnS nanocomposites exhibited both magnetic and photoluminescent properties. 相似文献
18.
Hemisphere-like F-doped anatase TiO2 has been synthesized by hydrothermal treatment of TiF4 aqueous solution in the presence of starch at 130 °C for 10 h, and then calcined at 450 °C for 2.5 h in air. The as-synthesized
product has been investigated by photocatalytic reaction test and characterized by powder X-ray diffraction (XRD), scanning
electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray photoelectron
spectroscopy (XPS), and UV–Vis diffuse reflectance spectra (DRS). The results showed that fluorine was successfully doped
into the TiO2 hemispheres. The F-doped TiO2 hemispheres showed high visible light activity in degradation of acid orange II, which could be attributed to the creation
of oxygen vacancies and good crystallinity. 相似文献
19.
Priya Thakur Ridhima Chadha Nandita Biswas Sisir K. Sarkar Tulsi Mukherjee Satyawati S. Joshi Sudhir Kapoor 《Materials Research Bulletin》2012,47(7):1719-1724
This report aimed to study the effect of CdS doping in TiO2 on the phase transformation of TiO2 from anatase to rutile using X-ray diffraction (XRD) and Raman spectroscopy. CdS-doped TiO2 nanocomposites have been prepared and characterized using Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). We have observed that contrary to bare TiO2, phase transformation of TiO2 from anatase to rutile is hindered when doped with CdS at high temperature. Raman spectroscopy is found to be more sensitive for detection of the surface of TiO2 as compared to XRD. 相似文献
20.
A novel bi-functional photorefractive (PR) poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl with carbazolyl fragments and chromophoric azophenyl was synthesized by a post azo coupling reaction and characterized by 1H NMR, elemental analysis, UV–Vis absorption and FTIR spectroscopy. Then chemical hybridized poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl-CdS nanocomposites with different molar ratio of CdS to poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl were prepared. It was confirmed that the CdS particles had a nanoscale size and quantum confinement effect adopting transmission electron microscopy and UV–Vis absorption spectroscopy. The generation of photocurrent on illumination and photoconductive properties of the nanocomposites were studied. Significant enhancement in photoconductivity induced by the chemical doping of CdS in poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl has also been demonstrated. 相似文献