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1.
TiO2 powder and TiO2 thin film on the surface of glazed ceramic tile were prepared by sol-gel method. The influences of different doping Cr3+ concentration on the photocatalytic activity of TiO2 were discussed, UV-visible and X-ray diffraction analysis were used to test the performance of TiO2 powder and film. The results indicate that photocatalytic activity of doping Cr3+-TiO2 thin film is higher than that of powder, and the interaction between Cr3+-doped and substrate can greatly enhance the photocatalytic activity. The results of X-ray diffraction and photoabsorption
show that the Cr3+-doped energy level in TiO2 is 0.62 eV high from the top of valence band, which belongs to the type of deep energy level doping. On the basis of the
semiconductor energy level theory and Cr3+ dopant energy level, the semiconductor energy level model of Cr3+ in TiO2 powder and thin film were established, and the doping mechanisms of Cr3+-doped in TiO2 powder and thin film were analyzed.
Foundation item: Project (20466001) supported by the National Natural Science Foundation of China 相似文献
2.
李宏 《武汉理工大学学报(材料科学英文版)》2007,22(3):482-485
The golden and ultraviolet-absorbed CeO2-TiO2 film was prepared on soda-lime glass substrate with the thickness of 2 mm via the sol-gel method. The transmission spectra in range of 200 nm-800 nm were measured, and the crystallization, the abrasion and acid resistance were also investigated. The appropriate sol contents and heat-treatment schedule were determined. The results indicate that the appropriate molar ratio of Ce/Ti was 3:5 to 5:6. The ultraviolet-absorbance ability increased with the increase of the Ce/Ti molar ratio, but when the Ce/Ti molar ratio was higher than 1.5, the homogeneity of the film was deteriorated. With the increase of heat-treatment temperature, the main wavelengths of the color of the coated glasses were equal, but the color' s saturation decreased; the transmission peaks were the same, while the intensity of the peaks decreased. The roughness, abrasion and acid resistance of the film were also enhanced at the same time. The appropriate heat- treatment temperature may be 340℃. 相似文献
3.
彭菊村 《武汉理工大学学报(材料科学英文版)》2006,21(4):105-107
A method of QWI ( quantum well intermixing) realizing through plasma-enhanced chemical vapordepositiom (PECVD) SiO2 film following ion implantation was investigated. PECVD 200 nm SiO2 film after 160 keV phosphorus(P) ion implantation was performed to induce InP-based multiple-quantum-well (MQW) laser structural intermixing, annealing process was carried out at 780 ℃ for 30 seconds under N2 flue, the blue shift ofphotoluminescence (PL) peak related to implanted dose: 1 × 1011 , 1 × 1012, 1 × 1013 ,3 × 1013 , 7 × 1013 ion/ cm2 is 22 nm, 65 nm, 104 nm, 109 nm, 101 nm, respectively. Under the same conditions, by comparing the blue shift of PL peak with P ion implantation only, slight differentiation between the two methods was observed, and results reveal that the defects in the implanting layers generated by ion implantation are much more than those in SiO2 film. So, the blue shift results mainly from ion implantation. However , SiO2 film also may promote the quantum well intermixing. 相似文献
4.
The effect of annealing on microstructure, adhesive and frictional properties of GeSb2Te4 films were experimentally studied. The GeSb2Te4 films were prepared by radio frequency (RF) magnetron sputtering, and annealed at 200℃ and 340℃ under vacuum circumstance, respectively. The adhesion and friction experiments were mainly conducted with a lateral force microscope (LFM) for the GeSb2Te4 thin films before and after annealing. Their morphology and phase structure were analyzed by using atomic force microscopy (AFM) and X-ray Diffraction (XRD) techniques, and the nanoindention was employed to evaluate their hardness values. Moreover, an electric force microscope (EFM) was used to measure the surface potential. It is found that the deposited GeSb2Te4 thin film undergoes an amorphous-to-fcc and fcc-to-hex structure transition; the adhesion has a weaker dependence on the surface roughness, but a certain correlation with the surface potential of GeSb2Te4 thin films. And the friction behavior of GeSb2Te4 thin films follows their adhesion behavior under a lower applied load. However, such a relation is replaced by the mechanical behavior when the load is relatively higher. Moreover, the GeSb2Te4 thin film annealed at 340℃ presents a lubricative property. 相似文献
5.
Mg fi lms of various thicknesses were deposited on Si(111) substrates at room temperature by resistive thermal evaporation method, and then the Mg/Si samples were annealed at 40 ℃ for 4 h. The effects of Mg fi lm thickness on the formation and structure of Mg2Si fi lms were investigated. The results showed that the crystallization quality of Mg2Si fi lms was strongly infl uenced by the thickness of Mg fi lm. The XRD peak intensity of Mg2Si(220) gradually increased initially and then decreased with increasing Mg fi lm thickness. The XRD peak intensity of Mg2Si(220) reached its maximum when the Mg fi lm of 380 nm was used. The thickness of the Mg2Si fi lm annealed at 400 ℃ for 4 h was approximately 3 times of the Mg fi lm. 相似文献
6.
GeS6 chalcogenide amorphous fi lm was deposited on glass substrate via PLD(pulsed laser deposition) technique. The performance and structure of the fi lm was characterized by XRD(X-ray diffraction), SEM(Scanning Electron Microscopy), EDS(Energy Dispersive Spectroscopy), optical transmission spectra, and Raman spectra, etc. The GeS6 amorphous fi lm was irradiated by 532 nm linearly polarized light, and its photoinduced darkening was investigated. The results showed that the GeS6 chalcogenide amorphous fi lm was smooth and compact with uniform thickness and combined with the substrate fi rmly, and its chemical composition was in consistency with the bulky target. When laser energy was fi xed, the transparence of the fi lm declined with the increase of the laser irradiation time. Obvious photo-induced darkening and relaxation phenomenon of the fi lm after laser irradiation were observed in this investigation. 相似文献
7.
TiO2 fims have been deposited on glass substrates using DC reactive magnetron sputtering at different oxygen partial pressures
from 0. 10 Pa.to 0.65 Pa. The transmittance (UV-vis) and photoluminescence (PL) spectra of the films were recorded. The results
of the UV-vis spectra show that the deposition rate of the films decreased at oxygen partial pressure P(O2)≥0.15 Pa, the band gap increased from 3.48 eV to 3.68eV for direct transition and from 3.27 eV to 3.34 eV for indirect transition
with increasing the oxygen partial pressure. The PL spectra show convincingly that the transition for films was indirect,
and there were some oxygen defect energy levels at the band gap of the films. With increasing the O2 partial pressure, the defect energy levels decreased. For the films sputtered at 0.35 and 0.65 Pa there were two defect energy
levels at 2.63 eV and 2.41 eV, corresponding to 0.72 eV and 0.94 eV below the conduction band for a band gap of 3.35 eV, respectively.
For the films sputtered at 0.10 Pa and 0.15 Pa, there was an energy band formed between 3.12 eV and 2.06 eV, corresponding
to 0.23 eV and 1.29 eV below the conduction band.
ZHAO Qing-nan : Born in 1963
Funded by Natural Science Foundation of Hubei Province, China. 相似文献
8.
TiO2 photocatalysts loaded with V2O5 were prepared via a modified hydrolysis process, and characterized by X-ray diffraction, transmission electron microscopy,
Raman spectra and diffuse reflectance UV-Vis spectra measurements. The photocatalytic activity of V2O5/TiO2 was investigated by employing splitting of water for O2 evolution. The results indicate that V2O5 loading can pronouncedly improve the photocatalytic activity of TiO2 with Fe3+ as an electron acceptor under UV or visible light irradiation. The optimum mass fraction of the loaded V2O5 is 8%, and the largest speed of O2 evolution for 8%V2O5 (mass fraction) loaded TiO2 catalyst is 118.2 μmol/(L·h) under UV irradiation, and 83.7 μmol/(L·h) under visible light irradiation. 相似文献
9.
(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs) were prepared by in-situ reaction, in which ethyl-orthosilicate (TEOS) was catalyzed by HCl and NH3·H2O, respectively. The ionic conductivity, the contact angle and the morphology of inorganic particles in the CPEs were investigated by AC impedance spectra, contact angle method and TEM. The conductivities of acid-catalyzed CPE and alkali-catalyzed CPE are 2.2×10^-5 and 1.1×10^-5 S/cm respectively at 30 ℃. The results imply that the catalyst plays an important role in the structure of in-situ preparation of SiO2, and influences the surface energy and conductivity of CPE films directly. Meanwhile, the ionic conductivity is related to the surface energy. 相似文献
10.
GONG Yueqiu TAO Haizheng ZHAO Xiujian 《武汉理工大学学报(材料科学英文版)》2006,21(2):139-141
To find materials with larger second-order nonlinearity, the Ge-P-S chalcogenide glasses with various ratios of GeS2 : P2S5 were prepared by the melt-quenching method. The microstructure and optical properties of these glasses were characterized by XRD, Raman, Vis- NIR speetroscopy and Maker fringe technique. The second harmonic generation (SHG) was observed in the as-prepared chalcogenide glasses which was ascribed to the thermal stress gradient and/ or the rnicroanisotropic defects ( such as the lone-pair orbital or the valence alternative pairs ) prefer-orientation of the as-prepared glasses. 相似文献
11.
PEO-LiClO4-TiO2 composite polymer electrolyte films were prepared. TiO2 was formed directly in matrix by hydrolysis and condensation reaction of tetrabutyl titanate. The crystallinity, morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry, scanning electron microscopy, atom force microscopy and alternating current impedance spectroscopy, respectively. The glass transition temperature and the crystallinity of composite polymer electrolytes are decreased compared with those of PEO-LiClO4 polymer electrolyte film. The results show that TiO2 particles are uniformly dispersed in PEO-LiClO4-5%TiO2 composite polymer electrolyte film. The maximal conductivity of 5.5×10^-5 S/cm at 20℃ of PEO-LiClO4-TiO2 film is obtained at 5% mass fraction of TiO2. 相似文献
12.
采用高温熔融法制备了Tb3+掺杂ZnO-B2O3-SiO2玻璃,通过荧光光谱、余辉衰减曲线、热释发光光谱以及紫外-可见吸收光谱等方法的测试分析,系统地研究了该玻璃体系的长余辉发光机理,并建立了其长余辉发光的半程隧穿模型.Tb3+掺杂ZnO-B2O3-SiO2玻璃的长余辉发光只跟能级较浅的电子陷阱有关,不同能级深度的陷阱对应着余辉衰减的不同过程;Tb3+离子是被紫外光直接激发发生光氧化失去电子的,然后电子经由导带被能级深度不同的电子陷阱捕获;电子从陷阱中热致逃逸出来后,通过5d能带隧穿到与陷阱最邻近的激活离子上而复合发光. 相似文献
13.
It was reported that both dielectricity and magnetism at room temperature were appreciably improved in Bi4Fe2TiO12 film compared with Bi4Fe2TiO12 bulk. X-ray diffraction profiles reveal similar crystalline nature and random orientation of the two, but X-ray photoelectron spectroscopy (XPS) experiments indicate that it is 1.4 eV lower binding energy of core-state O1s in the film relative to that of the bulk, so the improvement of multiferroics in the film is attributed to oxygen vacancies and high fraction of interface. The results have promising applications in multifunctional integrated devices. 相似文献
14.
The stoichiometric vanadium(IV) oxide thin films were obtained by controlling the temperature, time and pressure of annealing. The thermochromic phase transition and the IR thermochromic property of 400 nm and 900 nm VO2 thin films in the 7.5 μm-14 μm region were discussed. The derived VO2 thin film samples were characterized by Raman, XRD, XPS, AFM, SEM, and DSC. The resistance and infrared emissivity of VO2 thin films under different temperature were measured, and the thermal images of films were obtained using infrared imager. The results show that the VO2 thin film annealed at 550 ℃ for 10 hours through aqueous sol-gel process is pure and uniform. The 900 nm VO2 thin film exhibits better IR thermochromic property than the 400 nm VO2 thin film. The resistance of 900 nm VO2 film can change by 4 orders of magnitude and the emissivity can change by 0.6 during the phase transition, suggesting the outstanding IR thermochromic property. The derived VO2 thin film can control its infrared radiation intensity and lower its apparent temperature actively when the real temperature increases, which may be applied in the field of energy saving, thermal control and camouflage. 相似文献
15.
为了揭示SO2-4对块体纳米晶铜耐蚀性能的影响规律,利用电化学方法,结合X射线衍射、能谱分析、扫描电镜等表面分析技术,研究了惰性气体沉积原位温压法制备的块体纳米晶铜在不同质量分数(0.3%、1.3%、2.3%、3.3%和4.3%)Na2SO4溶液中的阳极极化行为.结果表明,随着SO2-4的增多,纳米晶铜的致钝电流密度增大,而致钝电位降低.在0.3%的Na2SO4溶液中加入1%的NaCl,纳米晶铜阳极极化行为发生明显变化,Cl-在纳米晶铜表面形成难溶于水的CuCl保护钝化膜,纳米晶铜致钝电流密度降低,活化-钝化过渡区电流密度下降速率显著减小. 相似文献
16.
以MoS_2为原料,通过超声波辅助液相剥离块体MoS_2,得到了MoS_2纳米片。将其分散于乙醇中,然后旋涂至氟掺杂氧化锡(FTO)导电玻璃上,煅烧后得到MoO_3薄膜,并组装成电致变色器件,研究了器件的电致变色性能。结果表明,所制备出的MoO_3纳米片的厚度约为50~60 nm,所制备的电致变色器件在580 nm波长处,透过率调制幅度达到最大值16.2%,器件的着色时间为3.0 s,褪色时间为9.2 s。 相似文献
17.
Local segregation in Cu-In precursors and its effects on the element distribution and microstructures of selenized CuInSe2 thin films were investigated. Cu-In precursors with an ideal total mole ratio of Cu to In of 0.92 were prepared by middle
frequency alternating current magnetron sputtering with Cu-In alloy target, then CuInSe2 absorbers for solar cells were formed by selenization process in selenium atmosphere. Scanning electron microscope and energy
dispersive X-ray spectroscope were used respectively to observe the surface morphologies and determine the compositions of
both Cu-In precursors and CuInSe2 thin films. Their microstructures were characterized by X-ray diffractometry and Raman spectroscope. The results show that
Cu-In precursors are mainly composed of Cu11In9 phase with In-rich solid solution. Stoichiometric CuInSe2 thin films with a homogeneous element distribution and single chalcopyrite phase can be synthesized from a segregated Cu-In
precursor film with an ideal total mole ratio of Cu to In of 0.92. CuInSe2 thin film shows P-type conductivity and its resistivity reaches 1.2×103 Θ·cm.
Foundation item: Project(2004AA513023) supported by the National High Technology Research and Development Program of China 相似文献
18.
SrBi2.2 Ta2O9 (SBT) thin film with thickness of 2 μm was successfully prepared by sol-gel method, using strontium acetate semihydrate [Sr(CH3 COO)2 · 1/2H2O] and bismth subnitrate [BiO(NO3)], and tantalum ethoxide [Ta(OCH2CH3)5] as source materials, glacial acetic and ethylene glycol as solvents. The X-ray diffraction (XRD) and transmission electron
microscope(TEM) results indicate that SBT layer-perovskite phase obtained has to be single phase, SBT thin film is formed
after being annealed at 800 °C for for 1 min. The typical hysteresis loop of SBT thin film on Pt/Ti/SiO2/Si is obtained, and the measured polarization value of the SBT thin film is 4. 2 μ/C/cm2.
Foundation item: Project (HIT. 2001. 67) supported by the Scientific Research Foundation of Harbin Institute of Technology; project (50172012)
supported by the National Natural Science Foundation of China 相似文献
19.
用传统的熔融冷却法制备了适用于光纤拉制的As2S3玻璃,研究了其透过率、热学属性、拉曼特性和二阶非线性光学性能及其稳定性。结果表明,对As2S3玻璃进行热-电场极化处理后,可以观察到明显的二次谐波发生信号,但是其稳定性较弱。拉曼分析表明样品在极化前后无明显结构变化。在5 kV、100℃对样品极化处理40 min后可获得最强的二阶非线性极化率值为0.38 pm/V。通过引入微量Na+后,可明显增强二次谐波发生信号的稳定性,这将有利于其在红外光电器件中的实际应用。 相似文献
20.
60CeO2-40TiO2 thin films were deposited on soda-lime silicate glass substrates by R.F. magnetron sputtering. The effects of heat-treatment on the UV-absorption of the thin films were studied on the 60CeO2-40TiO2 thin film with the largest UV cut-off wavelength. The sample films with CeO2:TiO2=60:40 were heated at 773 K, 873 K, 973 K for 30 min. These films are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy and spectrometer (XPS). XRD analysis proves that the addition of TiO2 to CeO2 changed the crystalline state of CeO2. But the UV absorption effect of CeO2-TiO2 films with CeO2 crystallite phase is inferior to that of the amorphous phase CeO2-TiO2 films. XPS analysis also indicates that the amorphous phase CeO2-TiO2 films have the most Ce3+ content in these films. Amorphous phase and crystalline phase of the CeO2-TiO2 films have different effects on UV absorption of the thin films. 相似文献