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1.
Sb-doped SnO2 (ATO)-(CeO2-TiO2) thin Films were deposited on glass substrates using the mixed solution including CeO2-TiO2 precursor and ATO particles by sol-gel dip coating process. ATO particles were prepared using low-temperature hydrothermal process. The mixed molar ratio of ATO to (CeO2-TiO2) vs the properties of CeO2-TiO2 thin film was investigated. The optical properties of the films were characterized by UV-visible transmission and infrared reflection spectra, the sheet resistance of ATO particles and films were measured by rubber sheeter (MYI-50) and four-point probe (HisuperGroup Inc, SDY-5), the surface morphology and structure of the films were analyzed using 3D Digitale Mikroskop and X-ray diffraction (XRD), respectively. The results showed that the ATO precursor solution lost weight completely at about 500 °C, and the ATO particles was obtained, which indicated the same rutile lattice structure as SnO2. The glass substrates coated with ATO-(CeO2-TiO2) thin films showed better properties in antistatic electricity (104-106 Ω/?), shielding UV (almost 100%), visible light transmission (70%) and infrared reflection (>30%).  相似文献   

2.
Nd-doped (2%, 5%, 10% in mass ratio) SnO2 powders were prepared via a facile hydrothermal procedure. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) specific surface area analyzers. Results showed that the Nd-doped SnO2 samples had more uniform and smaller primary particles compared with the pure sample, the particle size of the doped SnO2 decreased gradually with the increase of Nd, and the specific surface area also increased with the increase of the doped Nd. When used as gas sensing materials, the 5% and 10% Nd-doped sample showed high sensitivity and selectivity to ethanol. Furthermore, the Nd-doped sample showed fast response and recovery time to ethanol gas. This could be attributed to their small diameter, large surface area and Nd element doping.  相似文献   

3.
Tin dioxide (SnO2) and La-doped (1%, 5%, 10% in mass ratio) SnO2 samples were prepared via a hydrothermal method. The as-prepared powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the particle size of SnO2 decreased gradually with the increase of the doped La element. When used as anode materials of Li ion battery, the La-doped samples exhibited better cycling performance than the pure SnO2, and the cycling performance of the La-doped samples got better and better with the increase of the doped La. The better electrochemical performance of the doped material could be attributed to the doping of La element, which not only enabled SnO2 powders to have a good dispersivity but also reduced their particle size.  相似文献   

4.
Er was used as a dopant for the first time in preparing conductive powder to improve its performance. Er and Sb doped SnO2 conductive nanoparticles were prepared by the complexation-coprecipitation method with Sn, Sb2O3 and Er2O3 as the raw materials. Thermal behavior, crystal phase, and structure of the prepared conductive nanoparticles were characterized by TG/DSC, FTIR, XRD and TEM techniques, respectively. The resistivity of the prepared conductive nanoparticles was 0.29 Ω·cm; TG/DSC curves showed that the precursors lost weight completely before 750 °C; FTIR spectrum showed that the vibration peak were wide peak in 711 × 600 cm−1; the Er and Sb doped SnO2 conductive nanoparticles had intense absorption in 4000 × 1600 cm−1; Er and Sb doped SnO2 had a structure of tetragonal rutile; complex doping was achieved well by complexation-coprecipitation method and was recognized as replacement doping or caulking doping; TME showed that the particles were weakly agglomerated, the size of the particles calcined at 800 °C ranged approximately from 10 to 30 nm.  相似文献   

5.
Y was used as a dopant in preparing conductive powder to improve its performance. Y and Sb co-doped SnO2 conductive nanoparticles were prepared by the complexation-coprecipitation method with Sn, Sb2O3 and Y2O3 as the raw materials. Crystal phase, thermal behavior and structure of the prepared conductive nanoparticles were characterized by X-ray diffraction (XRD), thermal analysis (TG-DSC), Fourier transform infrared (FTIR) and transmission electron microscopy (TEM) techniques, respectively. The Y and Sb co-doped SnO2 conductive nanoparticles with a structure of tetragonal rutile had intense absorption in 4000-2500 cm?1, and the diameter ranged from 10 to 30 nm. The resistivity of Y and Sb co-doped SnO2 conductive nanoparticles was as low as 0.09 Ω·cm which was 4.6 times lower than that of Sb doped SnO2 conductive nanoparticles.  相似文献   

6.
This study focuses on the critical surface tension of lead sulfite (PbSO3) crystalline thin film produced with chemical bath deposition on substrates (commercial glass).The PbSO3 thin films were deposited at room temperature at different deposition times. The structural properties of the films were defined and examined according to X-ray diffraction (XRD) and the XRD results such as dislocation density, average grain size, and no. of crystallites per unit area. Atomic force microscopy was used to measure the film thickness and the surface properties. The critical surface tension of the PbSO3 thin films was measured with an optical tensiometer instrument and calculated using the Zisman method. The results indicated that the critical surface tension of films changed in accordance with the average grain size and film thickness. The film thickness increased with deposition time and was inversely correlated with surface tension. The average grain size increased according to deposition time and was inversely correlated with surface tension.  相似文献   

7.
The humidity sensing properties of La3+/Ce3+-doped TiO2-20 wt.%SnO2 thin films were studied.Sol-gel method was employed to prepare the films on alumina substrates.By constructing a humidity-impedance measuring system,the sensing behaviors were inspected for the films sintered at different temperatures.Experimental results showed that,0.5 wt.% of La2O3 or Ce2O3 doped films sintered at 500 °C for 2 h had the best humidity sensing properties,the impedance decreasing from 109 ? to below 104 ? in the humidity range of 15-95 RH%.Moreover,Ce3+-doping had better humidity sensing properties than La3+-doping.The doping mechanism was discussed in terms of phase composition,granularity of crystalline and segregation of rare earth ions at grain boundaries.  相似文献   

8.
Copper zinc tin sulfide (Cu2ZnSnS4) has been receiving a lot of attention in recent years as a new, alternative absorber for the production of cheap thin film solar cells owing to the high natural abundance of all the constituents, its tunable direct-band-gap energy, and its large optical absorption coefficient. In addition, to overcome the problem of expensive vacuum-based methods, solution-based approaches are being developed for Cu2ZnSnS4 deposition. In this study, Cu2ZnSnS4 thin films were grown on soda lime glass substrates via the sulfurization of solution grown Cu2SnS3/ZnS stacked sulfide layers. A new facile route to overcome the difficulty of depositing Cu2ZnSnS4 thin film with a desired stoichiometric composition in a single cation solution has been presented. The influences of deposition cycles of layers on the morphological, compositional, structural, and optical properties of the samples were investigated. It was observed from scanning electron microscopy (SEM) images that the films were continuous and composed of homogenously distributed large grains. Possible chemical formulations of the best samples were predicted to be Cu1.99Zn1.25Sn1.00S3.76 and Cu1.97Zn1.03Sn1.29S3.71 via energy-dispersive X-ray spectroscopy (EDXS) results. The X-ray diffraction (XRD) patterns of the samples matched very well with the reference values. The Raman-scattering analysis of the films proved the phase purity of the CZTS samples. The optical absorption coefficient of the films was found to be about 10cm?1 based on absorbance spectroscopy. The optical band gaps of the films were estimated to be between 1.36 and 1.50 eV. From these we are able to conclude that CZTS thin films can be effectively obtained via the vacuum-atmosphere sulfurization of Cu2SnS3/ZnS stacked sulfide layers.  相似文献   

9.
Undoped and Zn-doped Sn2S3 thin films were fabricated by spray pyrolysis technique on glass substrates kept at 400 °C. All the films exhibited orthorhombic crystal structure with a preferential orientation along the (2 1 1) plane. Nanoplate structures were observed from the SEM images and the presence of Zn in the doped films was confirmed from the EDX spectra. The average optical transmittance of all the films in the visible region was found to be nearly equal to 80 %. Film resistivity initially decreased from 3.27 × 10?1 to 0.78 × 10?1 Ω-cm for the Sn2S3 thin film doped with 1 wt% Zn concentration and for higher doping concentration it increased. The obtained results showed that the Sn2S3 thin film doped with 1 wt% Zn concentration had better physical properties which made them suitable for photovoltaic applications.  相似文献   

10.
The Y, F, and Ag tridoped TiO2/SnO2 composite nanocrystalline film (YFAg–TS) with prominent photocatalytic performance was prepared by the modified sol–gel method and was characterized by utilizing X-ray diffraction (XRD), differential thermal and thermogravimetric (DTA–TG) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) method, ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), and photoluminescence (PL). The XRD and DTA–TG results expose that the YFAg–TS catalyst is a mixed phase consisting of anatase, rutile, and chlorargyrite, which is beneficial to improving the photocatalytic performance of TiO2. The SEM, TEM, and BET results disclose that the YFAg–TS film has smaller nanoparticles, higher specific surface area, and narrower pore size compared with pure TiO2 film. The XRD and TEM results exhibit that a part of yttrium can enter the TiO2 lattice to induce lattice distortion. The XPS results confirm the presence of Y3+ state in the YFAg–TS sample, and Y3+ ions can act as the trapping site of electrons to expedite the separation of electrons and holes. The UV–vis DRS results reveal that the YFAg–TS film has an obvious absorption edge shift and a narrower bandgap (2.70 eV) compared with pure TiO2 film. The PL results show that the YFAg–TS film has the highest photogenerated electrons and holes separation efficiency and charges transfer efficiency among all samples. The photocatalytic activity of the YFAg–TS was assessed by monitoring the degradation of methyl green and formaldehyde solution. The results manifest that the YFAg–TS film has high stability and excellent photocatalytic performance. The possible synergistic photocatalytic mechanism of YFAg–TS films has been discussed in this paper.  相似文献   

11.
Pure SnO2 and Ce-doped (1%, 4%, 7%, 10% in mass ratio) SnO2 powders were prepared by a simple sol-gel method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) specific surface area analyzers. Results showed that the 7% Ce-doped sample has a particle size of 0.1-0.3 μm with a narrow particle size distribution while the pure SnO2 was consisted of large agglomerated particles with a diameter up to several micrometers. When used as the catalyst to degrade methyl orange (MO), the 7% Ce-doped sample showed best photocatalytic property. These properties can be attributed to the large surface area and small particle size of the 7% Ce-doped sample.  相似文献   

12.
The present work deals with a new series of silver-ion conducting nanocomposite gel polymer electrolytes based on poly (ethylene oxide)50silver triflate, (PEO)50AgCF3SO3 incorporated with a nano-sized inorganic filler namely, SnO2 and a plasticizer, ethylene carbonate (EC) prepared using solution casting technique. Electrical conductivity measurements have been made on thin film polymer electrolyte systems containing (PEO50AgCF3SO3: 2wt% SnO2) + x wt% EC (x = 10, 15, 20, 25 and 30 respectively). It has been found that the room temperature ionic conductivity value enhanced from 3.1 × 10?6 to 5.4 × 10?5 S cm?1 on addition of EC into the chosen nanocomposite system PEO50AgCF3SO3: 2wt% SnO2. The apparent surface morphology has been examined through scanning electron microscopic (SEM) analysis. The occurrence of a reduction in the degree of crystallinity of the plasticized system has also been revealed from the observed X-ray diffraction (XRD) data.  相似文献   

13.
There are two major weaknesses for the AgSnO2 contacts used in the low voltage switch devices. One is poor workability, which causes the AgSnO2 materials to hardly deform into the required shape. Another is the increased contact resistance after arcing, which, in turn, causes an unfavorable temperature rise in the switches. In this article, the nanocomposited AgSnO2 materials were developed to overcome the weaknesses. The nanosized SnO2 powders with or without CuO additive were prepared by the chemical precipitation method. The SnO2 powders and Ag powders were high energy milled together to obtain AgSnO2 composite powders, which were then sintered, hot pressed and extruded. It was found that the SnO2 particles mainly distribute in the interior of Ag grains with Ag film on the grain boundary. The hardness of AgSnO2 composites and the wetting angle of Ag melt on SnO2 particles decreased with the addition of a small amount of CuO. By the combining effect of Ag film on grain boundary and the addition of CuO, the elongation and workability of the AgSnO2 materials improved. The experiments of rapid solidification revealed that more SnO2 particles with CuO addition were engulfed in the Ag matrix than those without CuO, which inhibited the redistribution of SnO2 particles on the contact surface during the arcing process. The industrial type test in the 45A contactor suggested that the nanocomposited AgSnO2 materials are suitable to be used as contacts in low voltage switches.  相似文献   

14.
La2 Sn2 O7/SnO2 powder was synthesized by chemical co-precipitation method,and Ag-La2 Sn2 O7/SnO2 composites were prepared by hot-pressing sintering.The electrical resistivity,density,Brinell hardness and flexural strength of Ag-La2 Sn2 O7/SnO2 composites were measured.Moreover,the effect of La2 Sn2 O7 content on the arc erosion beha...  相似文献   

15.
An investigation has been conducted into the structural disordering in WC thin films induced by SiC additions. The effect of this disordering on film hardness is also reported. In this investigation, WC-SiC films with a SiC content varying from 11.6 to 38.2 pct were deposited using dual rf magnetron sputtering. The relative Si and W content in the films was determined using electron microprobe analysis. Analysis by X-ray diffraction (XRD) confirmed that, within this compositional range, the film structure transformed from crystalline to amorphous. The XRD patterns showed that the crystalline films consisted primarily of WC1−x , along with a small amount of W2C; no clear evidence for a separate crystalline SiC phase was found. High-resolution transmission electron microscopy (HRTEM) studies showed that with a lower Si content, the films consisted of crystallites 3 to 5 nm in diameter embedded in an amorphous phase. As the Si content increased, the amorphous phase content increased, both as interlayers between crystallites and as particles within the crystallites. Further Si increases led to a structure consisting of a high density of interconnected amorphous particles within well-defined semicrystalline domains separated by a thin amorphous interlayer. At the highest Si content, a clear two-phase morphology evolved, consisting of two nearly amorphous but distinct phases, which suggests a fine-scale partial-phase separation between the WC and the SiC. At the atomic level, it was found that Si decreased the coherence length within the crystalline phase, resulting in a structure of mixed crystalline/highly disordered phases scaled in the range of 2 to 4 nm. Despite the significant alterations in the film structures due to SiC additions, the hardness and modulus of the films were essentially constant within the compositional range of the transition, although films with SiC contents of less than ∼11 pct had significantly lower hardness levels. It is proposed that the effects of Si on hardness can be explained in terms of competition between the percolation threshold and the amorphization-inducing effect of Si.  相似文献   

16.
采用磁控共溅射方法分别制备了含有W和Mo两种不同成分的铜系薄膜,用EDX、XRD、SEM和纳米压痕仪对薄膜成份、结构、形貌和显微硬度进行了分析。结果表明,制备出的Cu—W和Cu-Mo薄膜均呈晶态结构,Cu-W和Cu—Mo形成了均匀的固溶体;经650℃热处理1h后,Cu—W和Cu—Mo薄膜中晶粒长大,有富w和富Mo相从基体Cu相中弥散析出;Cu-W薄膜的显微硬度随W成分的增加先增加后降低;Cu—Mo薄膜的显微硬度随Mo成分的增加而持续升高,薄膜退火态的显微硬度低于沉积态。分析认为,以上结果的产生均因添加W、Mo所引起的晶粒细化效应和薄膜的热稳定性较差所致。  相似文献   

17.
The nanocrystalline structure and mechanical properties of TaSi2 films deposited by sputtering of TaSi2 target have been investigated by x-ray diffraction, cross-sectional transmission electron microscopy (TEM), four-point electrical resistance measurement, and cyclic depth-sensitive nanoindentation. The purpose of this work is to study the formation of nanocrystalline structure in TaSi2 films on a silicon substrate. As revealed, a decrease in the deposition rate leads to an increase in the O and C impurity content in the films. Contamination of the film by O and C atoms during a low-rate deposition causes the formation of an amorphous phase in the deposited films. Upon annealing, the amorphous structures crystallize into mixtures of disilicide and a small amount of polysilicide, i.e. TaSi2 and Ta5Si3, respectively. After annealing at 970 K, the formation of a nanocrystalline structure with a grain size about 10 nm takes place in the film produced at a deposition rate of 0.2 nm/sec. The formation of a nanocrystalline structure changes drastically the mechanical properties of the film. The nanohardness and elastic modulus increase significantly, and the film becomes brittle and overstressed. After deposition in the film produced at the 1 nm/sec deposition rate mainly Ta disilicide and the amorphous phase are observed. After annealing, the amorphous phase near the Si substrate coexists with column-shape grains of Ta disilicide of size 150 × 500 nm. The annealed thin film becomes nonuniform in thickness. The nanohardness and elastic modulus increase.  相似文献   

18.
The present work aimed to investigate the electrochemical properties of ITO substrates in propylene carbonate (PC) with 0.5 mol/L lithium perchlorate (LiClO4) medium in the presence of elaborated thin films of cerium dioxide pure and doped with manganese at varying percentages. Ce1–xMnxO2 (x = 0 wt%, 2 wt%, 4 wt% and 6 wt%) were successfully deposited by the spray pyrolysis (SP) technique on the glass substrate and ITO at 450 °C. The effects of manganese (Mn) doped thin films Ce1–xMnxO2 were studied and investigated by using different analyses namely X-ray diffraction (XRD) analysis, Raman spectroscopy method, UV–Vis spectrophotometer technique, atomic force microscopy (AFM) analysis and electrochemical properties. XRD data obtained present a polycrystalline with a face-centred cubic structure of fluorite type. Raman results of undoped and Mn doped thin films show two peaks at 465 and 600 cm?1, due to the formation of extrinsic oxygen vacancies by the incorporation of Mn into Ce1–xMnxO2 matrix. Energy dispersive spectroscopy (EDS) data show the presence of Ce, O, and Mn elements in the elaborated films. The AFM results reveal that the surface roughness decreases with increasing Mn rate. Further, band gap energy of thin films decreases with increasing in Mn rate due to the formation of defect state between valence and conduction band. The storage capacity of the elaborated Ce1–xMnxO2/ITO/PC + LiClO4 electrode reaches a maximum of 1.997 mF in the presence of 6 wt% of Mn.  相似文献   

19.
Nanocrystalline SnO2 powders were synthesized by hydrolysis and solvolysis of SnCl2 followed by a fast nucleation process in Teflon lined autoclave. The as prepared samples were calcined at 400 °C for 4 h to attain stable phase. The X-ray diffraction pattern confirms tetragonal crystal structure for both hydrothermally and solvothermally prepared nanoparticles and the average crystallite size is calculated to be 14 and 30 nm respectively. Williamson–Hall plot (W–H plot) reveals low value of strain induced broadening using uniform deformation model. Absorption co-efficient of prepared SnO2 was determined using UV–Visible absorption spectrum. Nyquist plane plot shows the decreased electrical resistance of SnO2 with increasing the applied potential resulting in increased conductivity. The increasing conducting behavior of tin oxide nanoparticles can be used as conducting layer in photoelectrodes.  相似文献   

20.
The high saturation induction makes Fe1?x Co x thin films desirable for use as recording head materials. In this experiment, Fe7Co3 thin films were deposited by DC cylindrical magnetron sputtering using the different position of glass substrate in argon pressure of 2 × 10?2 Torr under sputtering power of 120 W. The magnetic properties were determined by scanning probe microscopy. The surface morphology and r.m.s roughness of thin films were analyzed using atomic force microscopy and the optical properties have been analyzed by spectrophotometer. The thin film thickness, grain size and optical properties were affected by changing substrate position and we found the deposition influenced magnetic properties and surface morphology.  相似文献   

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