The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The c...The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (icorr) and the polarization resistance (Rp) of Ni-P/TiO2 film are 0.22 μA/cm2 (about 14% of that of Ni-P coating),and 120 kΩ·cm2 (about 2 times of that of Ni-P coating),respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.展开更多
In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performanc...In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.展开更多
Different semiconductive SiC foam supports were prepared by varying the sintering temperature and atmosphere, and with or without alkaline solution treatment and high temperature oxidation following a macromolecule py...Different semiconductive SiC foam supports were prepared by varying the sintering temperature and atmosphere, and with or without alkaline solution treatment and high temperature oxidation following a macromolecule pyrogenation combined with reaction bonding method. Nano-TiO2 particles were immobilized onto these SiC foam supports by a composite sol-gel method. The phase, surface morphology, the type of conduction and the photocatalytic activity of the TiO2-SiC composite photocatalysts were studied. The TiO2 coated on p-type Si-free SiC support showed the highest photocatalytic efficiency in degradation of 4- aminobenzenesulfonic acid (4-ABS) in aqueous solution as compared to that coated on n-type SiC support and p-type SiC supports with residual Si or Si02 on the surface. The result showed that the TiO2 coatings immobilized on p-type semiconductive SiC foam supports exhibited obviously higher photocatalytic activity in comparison to that coated on n-type SiC foam support. The p-n heterojunctions formed between the p-type SiC supports and n-type TiO2 coatings might be able to account for the better charge separation and transfer as well as the photocatalytic activity of the TiO2-SiC composite photocatalyst.展开更多
TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase ...TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase transformation of TiO 2 and the effect of composite mode of SnO 2 on phase transformation of TiO 2 have been investigated by TG-DTA and XRD. The phase transform of pure TiO 2 from anatase to rutile begins at 750 ℃ and the presence of SnO 2 markedly reduces the transform temperature: for coated SnO 2-TiO 2 composite with ω(SnO 2)=20% it was 400 ℃. The SnO 2/TiO 2 composite prepared by precipitation method and followed by calcination at 400 ℃ for 30 min possesses 55% rutile TiO 2. The formation of SnO 2-TiO 2 solid- solution occurrs mainly due to the substitution of Ti 4+ crystal lattice sites by Sn 4+ ions of SnO 2.展开更多
基金Sponsored by Hi-Tech Research and Development Program of China (2003AA305120)
文摘The Ni-P/TiO2 composite film on sintered NdFeB permanent magnet was investigated by X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM),and energy dispersive X-ray spectrometer (EDX). The corrosion resistance of Ni-P/TiO2 film coated on NdFeB magnet,in 0.5 mol/L NaCl solution,was studied by potentiodynamic polarization,salt spray test and electrochemical impedance spectroscopy (EIS) techniques. The self-corrosion current density (icorr) and the polarization resistance (Rp) of Ni-P/TiO2 film are 0.22 μA/cm2 (about 14% of that of Ni-P coating),and 120 kΩ·cm2 (about 2 times of that of Ni-P coating),respectively. The anti-salt spray time of Ni-P/TiO2 film is about 2.5 times of that of the Ni-P coating. The results indicate that Ni-P/TiO2 film has a better corrosion resistance than Ni-P coating,and the composite film increases the corrosion resistance of NdFeB magnet markedly.
文摘In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.
基金supported by the National Key Technology R&D Program of China(Grant No.2011BAE03B07)
文摘Different semiconductive SiC foam supports were prepared by varying the sintering temperature and atmosphere, and with or without alkaline solution treatment and high temperature oxidation following a macromolecule pyrogenation combined with reaction bonding method. Nano-TiO2 particles were immobilized onto these SiC foam supports by a composite sol-gel method. The phase, surface morphology, the type of conduction and the photocatalytic activity of the TiO2-SiC composite photocatalysts were studied. The TiO2 coated on p-type Si-free SiC support showed the highest photocatalytic efficiency in degradation of 4- aminobenzenesulfonic acid (4-ABS) in aqueous solution as compared to that coated on n-type SiC support and p-type SiC supports with residual Si or Si02 on the surface. The result showed that the TiO2 coatings immobilized on p-type semiconductive SiC foam supports exhibited obviously higher photocatalytic activity in comparison to that coated on n-type SiC foam support. The p-n heterojunctions formed between the p-type SiC supports and n-type TiO2 coatings might be able to account for the better charge separation and transfer as well as the photocatalytic activity of the TiO2-SiC composite photocatalyst.
文摘TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase transformation of TiO 2 and the effect of composite mode of SnO 2 on phase transformation of TiO 2 have been investigated by TG-DTA and XRD. The phase transform of pure TiO 2 from anatase to rutile begins at 750 ℃ and the presence of SnO 2 markedly reduces the transform temperature: for coated SnO 2-TiO 2 composite with ω(SnO 2)=20% it was 400 ℃. The SnO 2/TiO 2 composite prepared by precipitation method and followed by calcination at 400 ℃ for 30 min possesses 55% rutile TiO 2. The formation of SnO 2-TiO 2 solid- solution occurrs mainly due to the substitution of Ti 4+ crystal lattice sites by Sn 4+ ions of SnO 2.