| Summary: | 碩士 === 國立中興大學 === 材料科學與工程學系所 === 107 === My laboratory has used ZrN as the working electrode and Pt as the counter electrode to successfully synthesize BaZrO3 by a hydrothermal-galvanic couple method. However, ZrN with different N2/Ar flow ratios were used to form hetero-conductive nitride thin film dual electrodes. The dual electrodes system is used to synthesize BaZrO3. Therefore, this research focuses on experiments by three kinds of electrode systems, mainly homo-nitride thin film dual electrodes (ZrN-ZrN), hetero-nitride film double electrodes (ZrN-TiN), and a single-ZrN electrode (ZrN-Pt) was used as a control group to investigate the discharge mechanism of the dual electrodes and the formation of an oxide film on the dual electrodes and to evaluation of photocurrent. Firstly, the different N2/Ar flow ratios were changed to synthesize ZrN with different characteristics by the unbalanced dc magnetron sputtering. ZrN was separately subjected to single-ZrN electrode hydrothermal-galvanic couple method. it was found that N2/Ar flow ratio increased. The reaction current also rises, and the crystallinity and photocurrent effect of synthesized BaZrO3 also increases. At the beginning of the reaction, ZrN will be formed into an amorphous material. it can be known that the amorphous substance is mainly ZrO(OH)2 by Raman scattering. As the reaction time increases, the product also passes from ZrO(OH)2 to a crystalline BaZrO3. The two types of ZrN with the largest difference in reaction current values are used for hydrothermal-galvanic couple method with homo-conductive nitride thin film dual electrodes. and the current value is lower than that of the single-ZrN electrode because the two ends of the electrode compete with each other to suppress. Reacting ZrN and TiN by hydrothermal-galvanic couple method with hetero-conductive nitride thin film dual electrodes has a current reversal phenomenon immediately after the start of the reaction, but this phenomenon does not exist in the homo-ZrN dual electrodes because ZrN grows in layers and ZrN will react until ZrN is exhausted. and BaTiO3 stops to synthesize when it covers the surface of TiN.
BaZrO3 was used as the photocurrent electrode material in this study. It was found that the photocurrent effect of BaZrO3 after 12 hours of reaction was higher than that of the reaction for 5 hours, due to BaZrO3 after 12 hours of reaction has two different materials which are amorphous layer and the crystalline layer. It forms a heterostructure layer, which can more effectively separate electron hole pairs, and the amorphous layer can provide abundant oxygen vacancies, generating local surface plasma resonance, resulting in enhanced photocurrent effect. In addition, the photocurrent effect of the homo-conductive ZrN dual electrodes is less than that of the single-conductive ZrN electrode electrode, and the crystallinity of BaZrO3 may be lower due to the suppression of the current of homo-conductive ZrN dual electrodes.
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