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961.
利用脉冲激光沉积技术,通过改变沉积过程中的氧气压力,在蓝宝石(0001)基片上制备了一系列ZnMgO合金.通过X射线衍射、反射和透射光谱以及室温和变温荧光光谱,对薄膜的结构和光学性能进行了系统地表征,分析了工作气压对ZnMgO合金薄膜的结晶质量及光学特性的影响.研究结果表明:随着沉积环境中氧气压力的增大,ZnMgO薄膜的结晶质量下降,富氧环境下,与蓝宝石晶格平行的ZnO晶粒的出现是导致薄膜结晶质量下降的主要原因;相对于本征ZnO,不同氧气环境下沉积的ZnMgO薄膜的紫外荧光峰均出现了不同程度的蓝移.随着工
关键词:
ZnO
Mg掺杂
脉冲激光沉积
薄膜生长
光学特性 相似文献
962.
Phase transition properties of a spin-1 Blume-Emery-Griffiths model (BEGM) with random transverse crystal field is studied by the effective field theory for a simple cubic lattice. In T−Dx space, we obtain the phase diagrams with the ratio α between the biquadratic interaction and the exchange interaction as well as a tunable parameter l of the transverse crystal field. The tricritical point (TCP) appears at α<0, which undergoes a crossover from positive to negative direction of the transverse crystal field when l<0. The TCP cannot be observed for α>0. The maximum critical temperature increases with the increase of α. The position of the peak value tends to the drift of negative or positive direction for a different magnitude or an imperfect (±) transverse crystal field distribution. In T−α space, the range of ordered phase is magnified when the ratio is changed from α<0 to α>0. The random transverse crystal field obviously affects the TCP. 相似文献
963.
CuO/tetrapod-like ZnO whisker (T-ZnOw) nanocomposites were successfully synthesized using a simple photo-deposition method. Some nanocomposites exhibit remarkably improved photocatalytic property, while the extents of the improvements vary with different Cu/Zn molar ratios and polyethylene glycol (PEG) concentrations. Moreover, it is found that excessively high Cu/Zn molar ratio or PEG concentration would reduce the photocatalytic property of the nanocomposites. A direct relationship between the morphology and the photocatalytic property of CuO/T-ZnOw was established and then analyzed by discussing the photocatalytic mechanism of the CuO/T-ZnOw nanocomposites. 相似文献
964.
Xue-Long HeMei Liu Guan-Jun YangSheng-Qiang Fan Chang-Jiu Li 《Applied Surface Science》2011,258(4):1377-1384
Flexible Pt counter electrodes (CEs) were prepared on indium-doped tin oxide coated polyethylene naphthalate (ITO-PEN) substrate by electroless deposition. The correlation between the microstructure and the property of the Pt CEs was investigated. Results showed that isolated Pt nanoparticles were uniformly distributed on the ITO surface at a short deposition duration, and then grew with the deposition duration, leading to the interconnection of adjacent Pt nanoparticles. The interconnection of Pt nanoparticles was beneficial to the electrical property of the Pt CEs, while it was unfavorable to the electrocatalytic property of the Pt CEs. A microstructure model was proposed to explain the correlation between the microstructure and the property of the Pt CEs. In addition, the Pt CEs showed low charge transfer resistance (1.66-0.58 Ω cm2), which was comparable to that (1.16 Ω cm2) of the conventional sputtered Pt CE. The high electrocatalytic property of the electroless deposited Pt CEs makes the assembled DSCs present comparable energy conversion efficiency of the DSCs using sputtered Pt CE. 相似文献
965.
Shijing WangBoping Zhang Cuihua ZhaoSongjie Li Meixia ZhangLiping Yan 《Applied Surface Science》2011,257(8):3358-3362
The cobalt oxide (CoO and Co3O4) thin films were successfully prepared using a spin-coating technique by a chemical solution method with CH3OCH2CH2OH and Co(NO3)2·6H2O as starting materials. The grayish cobalt oxide films had uniform crystalline grains with less than 50 nm in diameter. The phase structure is able to tailor by controlling the annealing atmosphere and temperature, in which Co3O4 thin film was obtained by annealing in air at 300-600, and N2 at 300, and transferred to CoO thin film by raising annealing temperature in N2. The fitted X-ray photoelectron spectroscopy (XPS) spectra of the Co2p electrons are distinguishable from different valence states of cobalt oxide especially for their satellite structure. The valence control of cobalt oxide thin films by annealing atmosphere contributes to the tailored optical absorption property. 相似文献
966.
Udai B. Singh D.C. AgarwalS.A. Khan Manish KumarA. Tripathi R. SinghalB.K. Panigrahi D.K. Avasthi 《Applied Surface Science》2011,258(4):1464-1469
Hydrophilic Ag nanostructures were synthesized by physical vapour deposition of 5 nm Ag thin films followed by irradiation with 1.5 keV Ar atoms. Optical absorbance measurements show a characteristic surface plasmon resonance absorption band in visible region. A blue-shift in absorbance from 532 to 450 nm is observed with increasing fluence from 1 × 1016 to 3 × 1016 atoms/cm2. Atomic force microscopy was performed for the pristine and irradiated samples to study the surface morphology. The atom beam irradiation induced sputtering and surface diffusion lead to the formation of plasmonic surface. Rutherford backscattering spectroscopy of the pristine and irradiated film indicates that metal content in the film decreases with ion fluence, which is attributed to the sputtering of Ag by Ar atoms. The contact angle measurement demonstrates the possibility of engineering the hydrophilicity by atom beam irradiation. 相似文献
967.
Co(OH)2 nanoparticles were synthesized using only CoSO4·7H2O and NaOH as reactants without other auxiliary reagents via a simple, low-cost and practical ball-milling technique and investigated as the active electrode materials for supercapacitors. The structure and morphology of the resulting Co(OH)2 samples were examined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM). The observations revealed the formation of brucite-like phase of β-Co(OH)2, which had an irregular sphere-like shape with an average size of 50-100 nm. When investigated as electrode materials for supercapacitors, the β-Co(OH)2 exhibited good energy-storage performances in terms of high specific capacitance of 599 F g−1 and excellent capacity retention, suggesting its potential application in the electrode material for supercapacitors. 相似文献
968.
The nanocrystalline samples of La0.9Sr0.1MnO3 (LSMO) have been prepared by the combustion method. The thermo gravimetric analysis of precursor was carried out. The X-ray diffraction study confirms the rhombohedral crystal structure without any other impurity phases. The morphology and magnetic properties change with annealing temperature. The saturation magnetization increases linearly and coercivity of the nanoparticles varies significantly as annealing temperature increases. The maximum saturation magnetization and lower coercivity found for the sample heat treated at 1200 °C are 52.5 emu/g and 10.7 Oe respectively. 相似文献
969.
970.
Xiao-Ping WeiXian-Ru Hu Bin LiuYi Lei Hong DengMing-Kun Yang Jian-Bo Deng 《Journal of magnetism and magnetic materials》2011,323(12):1606-1610
The first-principle calculations within density functional theory are used to investigate the electronic structure and magnetism of the Mn2ZnGe Heusler alloy with CuHg2Ti-type structure. The half-metallic ferrimagnets (HMFs) in Mn2ZnGe are predicted. The energy gap lies in the minority-spin band for the Mn2ZnGe alloy. The calculated total spin magnetic moment is −2μB per unit cell for Mn2ZnGe alloy, the magnetic moments of Zn and Mn(B) are antiparallel to that of Mn(A), and we also found that the half-metallic properties of Mn2ZnGe are insensitive to the dependence of lattice within the wide range of 5.69 and 5.80 Å where exhibiting perfect 100% spin polarization at the Fermi energy. 相似文献