A bond coat for thermal barrier coating (TBC), NiCrAlY coating, is subjected to vac-uum heat treatment in order to remove internal stress before ceramic top coat is de-posited. The effect of vacuum heat treatment on t...A bond coat for thermal barrier coating (TBC), NiCrAlY coating, is subjected to vac-uum heat treatment in order to remove internal stress before ceramic top coat is de-posited. The effect of vacuum heat treatment on the oxidation behavior of the sputtered NiCrAlY coating has been investigated. The as-sputtered NiCrAlY coating consists of γ-Ni and b-NiAl phases. After vacuum heat treatment, the sputtered NiCrAlY coating mainly consists of γ'-Ni3Al, β-NiAl, γ-Ni, and trace of α-Al2O3 phases. The isothermal oxidation of sputtered NiCrAlY coating with and without vacuum heat treatment has been performed at 1000℃. It is shown that a-Al2O3 formed during vacuum heat treatment acts as nuclei for the formation of a-Al2O3, and the protective a-Al2O3 scale is formed more rapidly on the vacuum heat treated NiCrAlY coating than that formed on the untreated coating. Also the a-Al2O3 scale has a better adherence to the vacuum heat treated NiCrAlY coating. Therefore the vacuum heat treatment improves the oxidation resistance of sputtered NiCrAlY coating.展开更多
Ru O2·n H2O film was deposited on tantalum foils by electrodeposition and heat treatment using Ru Cl3·3H2O as precursor.Surface morphology, composition change and cyclic voltammetry from precursor to amorpho...Ru O2·n H2O film was deposited on tantalum foils by electrodeposition and heat treatment using Ru Cl3·3H2O as precursor.Surface morphology, composition change and cyclic voltammetry from precursor to amorphous and crystalline RuO2·n H2O films were studied by X-ray diffractometer, Fourier transformation infrared spectrometer, differential thermal analyzer, scanning electron microscope and electrochemical analyzer, respectively. The results show that the precursor was transformed gradually from amorphous to crystalline phase with temperature. When heat treated at 300 °C for 2h, RuO2·n H2O electrode surface gains mass of2.5 mg/cm2 with specific capacitance of 782 F/g. Besides, it is found that the specific capacitance of the film decreased by roughly20% with voltage scan rate increasing from 5 to 250 m V/s.展开更多
BaPbO3 thin films were deposited on Al2O3 substrates by sol-gel spin-coating and rapid thermal annealing. The microstructure and phase of BaPbO3 thin films were determined by X-ray diffractometry, scanning electrons m...BaPbO3 thin films were deposited on Al2O3 substrates by sol-gel spin-coating and rapid thermal annealing. The microstructure and phase of BaPbO3 thin films were determined by X-ray diffractometry, scanning electrons microscopy and energy dispersive X-ray spectrometry. The influence of annealing temperature and annealing time on sheet resistance of the thin films was investigated. The results show that heat treatment, including annealing temperature and time, causes notable change in molar ratio of Pb to Ba, resulting in the variations of sheet resistance. The variation of electrical properties demonstrates that the surface state of the film changes from two-dimensional behavior to three-dimensional behavior with the increase of film thickness. Crack-free BaPbO3 thin films with grain size of 90 nm can be obtained by a rapid thermal annealing at 700 ℃ for 10 min. And the BaPbO3 films with a thickness of 2.5 μm has a sheet resistance of 35 Ω·-1.展开更多
该研究制备高电导、高透明的磷掺杂氢化纳米晶硅氧(nc-Si Ox:H)薄膜,应用于晶硅异质结(SHJ)太阳电池的窗口层以替代传统的氢化非晶硅(a-Si:H)薄膜。与以a-Si:H薄膜为窗口层的电池相比,短路电流密度提高0.5 m A/cm^(2),达到38.5 m A/cm^(...该研究制备高电导、高透明的磷掺杂氢化纳米晶硅氧(nc-Si Ox:H)薄膜,应用于晶硅异质结(SHJ)太阳电池的窗口层以替代传统的氢化非晶硅(a-Si:H)薄膜。与以a-Si:H薄膜为窗口层的电池相比,短路电流密度提高0.5 m A/cm^(2),达到38.5 m A/cm^(2),填充因子为82.7%,光电转换效率为23.5%。实验发现,在nc-Si Ox:H薄膜沉积前对本征非晶硅层表面进行处理,沉积1 nm纳米晶硅(nc-Si:H)种子层,可改善nc-Si Ox:H薄膜的晶化率,降低薄膜中的非晶相含量。与单层nc-Si Ox:H窗口层的电池相比,nc-Si:H/nc-Si Ox:H叠层结构提高电池填充因子,达到83.4%,光电转换效率增加了0.3%,达到23.8%。展开更多
基金The authors thank Prof.H. Y. Lou for sputtering NiCrAlY coating.
文摘A bond coat for thermal barrier coating (TBC), NiCrAlY coating, is subjected to vac-uum heat treatment in order to remove internal stress before ceramic top coat is de-posited. The effect of vacuum heat treatment on the oxidation behavior of the sputtered NiCrAlY coating has been investigated. The as-sputtered NiCrAlY coating consists of γ-Ni and b-NiAl phases. After vacuum heat treatment, the sputtered NiCrAlY coating mainly consists of γ'-Ni3Al, β-NiAl, γ-Ni, and trace of α-Al2O3 phases. The isothermal oxidation of sputtered NiCrAlY coating with and without vacuum heat treatment has been performed at 1000℃. It is shown that a-Al2O3 formed during vacuum heat treatment acts as nuclei for the formation of a-Al2O3, and the protective a-Al2O3 scale is formed more rapidly on the vacuum heat treated NiCrAlY coating than that formed on the untreated coating. Also the a-Al2O3 scale has a better adherence to the vacuum heat treated NiCrAlY coating. Therefore the vacuum heat treatment improves the oxidation resistance of sputtered NiCrAlY coating.
基金Project(S2013040015492)supported by the Natural Science Foundation of Guangdong Province,ChinaProject(2007AA03Z240)supported by Hi-tech Research and Development Program of China
文摘Ru O2·n H2O film was deposited on tantalum foils by electrodeposition and heat treatment using Ru Cl3·3H2O as precursor.Surface morphology, composition change and cyclic voltammetry from precursor to amorphous and crystalline RuO2·n H2O films were studied by X-ray diffractometer, Fourier transformation infrared spectrometer, differential thermal analyzer, scanning electron microscope and electrochemical analyzer, respectively. The results show that the precursor was transformed gradually from amorphous to crystalline phase with temperature. When heat treated at 300 °C for 2h, RuO2·n H2O electrode surface gains mass of2.5 mg/cm2 with specific capacitance of 782 F/g. Besides, it is found that the specific capacitance of the film decreased by roughly20% with voltage scan rate increasing from 5 to 250 m V/s.
基金Project(033177) supported by the Natural Science Foundation of Guangdong Province, ChinaProject(040140) supported by the Natural Science Foundation of South China University of Technology
文摘BaPbO3 thin films were deposited on Al2O3 substrates by sol-gel spin-coating and rapid thermal annealing. The microstructure and phase of BaPbO3 thin films were determined by X-ray diffractometry, scanning electrons microscopy and energy dispersive X-ray spectrometry. The influence of annealing temperature and annealing time on sheet resistance of the thin films was investigated. The results show that heat treatment, including annealing temperature and time, causes notable change in molar ratio of Pb to Ba, resulting in the variations of sheet resistance. The variation of electrical properties demonstrates that the surface state of the film changes from two-dimensional behavior to three-dimensional behavior with the increase of film thickness. Crack-free BaPbO3 thin films with grain size of 90 nm can be obtained by a rapid thermal annealing at 700 ℃ for 10 min. And the BaPbO3 films with a thickness of 2.5 μm has a sheet resistance of 35 Ω·-1.
