| Summary: | 碩士 === 南台科技大學 === 化學工程與材枓工程系 === 100 === This study have been successfully prepared the zinc oxide (ZnO) nano-size powders by precipitation method with ultrasonic irradiation. This work focuses the effects of the different power density of ultrasonic irradiation and alkali sources on the properties of ZnO powders. From these results of TGA, and FT-IR analysis showed that the urea as alkali source, the wurtzite structure of ZnO powders could be obtained by calcined at 400℃ for 2 hours with precursor powders. The crystal structure was found the prefer growth plane of (101), the grain size of ZnO powders was decreased with increasing of the power density of ultrasonic irradiation. The network-like of ZnO powders obtained with without ultrasonic irradiation, but the particles of ZnO powders are obtained with ultrasonic irradiation condition. Further, using of UV/visible spectroscopy and contact angle analyzed on the properties of ZnO films, the results showed that the UVA (320-380 nm) range of shelter and hydrophobic was increased with ultrasonic irradiation. On the photocatalytic efficiency test, the MB degradation rate using the power density ultrasonic irradiation of 40 Wcm-2 was 1.6 times higher than without ultrasonic irradiation.
When using ammonia as the alkali source, the rod-like pure phase of ZnO powders were obtained without calcining process with reaction temperature of 60℃. Furthermore, the aspect ratios (LID) of rod-like ZnO powders increased with increasing of power density of ultrasonic irradiation. Further, using of UV/visible spectroscopy and photocatalytic efficiency test analyzed on the properties of ZnO, the results showed that UVA transmittance was from 35.4% to 25.0% as increase the power density of ultrasonic irradiation, and the MB degradation rate was 2.1 times higher than without ultrasonic irradiation.
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