ZnO纳米阵列的制备、改性及性能研究

发布时间：2018-03-21 17:47

  本文选题：ZnO纳米阵列　切入点：刺突状CuO/ZnO纳米异质结　出处：《西南交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：新能源的开发以及环境治理是解决能源短缺与环境恶化的主要手段,开发治理成本高以及开发治理效果不明显仍是面临的主要问题。因此找到一种低成本的制备工艺和材料来有效的开发新能源以及治理环境具有实际的研究价值。本文采用水热法、化学浴以及光化学沉积法三种低成本的制备方法来制备ZnO纳米阵列及其复合阵列,期望能够为后续进一步低成本应用提供一个参考。本文研究内容主要包括以下三个方面：(1)采用水热法,以硝酸锌为锌源、六亚甲基四胺(HMTA)为OH-源、聚乙烯亚胺(PEI)为添加剂、蒸馏水为溶剂,在FTO导电玻璃基底上制备ZnO纳米阵列,系统研究了不同制备条件对合成ZnO纳米阵列的影响。结果表明,随着种子层溶液浓度增大,ZnO纳米阵列高度以及直径逐渐降低,垂直取向度逐渐增大,规整度增加；当Zn2+/HMTA摩尔浓度比逐渐增大时,纳米阵列高度逐渐降低,直径呈现先增后减的趋势,当摩尔比为5：5时,其光学禁带值与理论值接近为3.2 eV；随着前驱体溶液浓度增加,纳米阵列直径和高度呈逐渐增大的趋势,透射率逐渐降低,当前驱体溶液浓度为50和75 mM时,ZnO纳米阵列由六棱柱针状变向圆锥状转变；当反应温度增加时,纳米阵列直径和高度逐渐增大,透射率逐渐降低,并随着温度增加缺陷增多。当Zn2+/HMTA浓度摩尔比为5：5,前驱体溶液浓度为25 mM,反应温度增加为90℃时制备的ZnO纳米阵列,结晶性、规整度相对最好。(2)采用化学水浴法,以硝酸铜为铜源、酒石酸钾钠(PSTT)为络合剂、氢氧化钠和碳酸钠为碱性介质、甲醛为还原剂、蒸馏水为溶剂,在ZnO纳米阵列基底上制备刺突状CuO纳米颗粒,研究了不同制备条件对合成刺突状CuO/ZnO纳米阵列的影响。结果表明：当络合剂PSTT浓度逐渐增大时,在ZnO纳米阵列表面覆盖的CuO纳米颗粒逐渐增多,颗粒直径也随之增加,复合阵列透射率逐渐增加：当还原剂量逐渐增加时,ZnO纳米阵列表面覆盖CuO纳米粒子量逐渐减少,颗粒直径也逐渐降低,透射率透射率逐渐增加。当PSTT浓度为2.6 mM、甲醛量为0.125%v/v时制备的CuO/ZnO纳米异质结相对于纯ZnO纳米阵列在紫外光照射下表现出优异的光催化性能,对MO溶液降解率达到92.8%；同时在紫外可见光范围内其吸收边从380延伸至560 nm左右。(3)采用光化学沉积法,以硝酸铜为铜源、蒸馏水为溶剂,在ZnO纳米阵列端部制备花朵状CuO纳米粒子团簇结构,研究了不同制备条件对合成花朵状CuO/ZnO纳米异质结的影响。结果表明：当紫外光强度逐渐增大,阵列端部CuO纳米粒子团簇逐渐由棉絮状向刺突状转变,吸光度逐渐增强,缺陷减少；当铜源浓度增大,ZnO纳米阵列端部生长的CuO纳米粒子团簇逐渐增大,吸光度逐渐降低,缺陷逐渐增多。研究发现,当铜源浓度为3 mM,紫外光强为60 W时制备的花朵状CuO/ZnO纳米异质结阵列光降解MO效果最好。
[Abstract]:The development of new energy and environmental governance are the main means to solve the energy shortage and environmental degradation. Therefore, it is of practical value to find a low-cost preparation process and materials to effectively develop new energy and environmental governance. The hydrothermal method is used in this paper. Three low-cost preparation methods, chemical bath and photochemical deposition, were used to prepare ZnO nanoarrays and their composite arrays. It is expected to provide a reference for further low-cost application in the future. The main contents of this study include the following three aspects: hydrothermal method, zinc nitrate as zinc source, hexamethylenetetramine (HMTAA) as OH- source, polyethylene imine (PEI) as additive, and zinc nitrate as zinc source, hexamethylenetetramine (HMTAA) as OH- source, and polyethylene imine as additive. ZnO nanoarrays were prepared on FTO conductive glass substrate with distilled water as solvent. The effects of different preparation conditions on the synthesis of ZnO nanoarrays were systematically studied. With the increase of the concentration of seed layer solution, the height and diameter of ZnO nanoarrays decrease gradually, the vertical orientation degree increases and the regularity degree increases, and when the molar concentration ratio of Zn2 / HMTA increases, the height of the nanoarrays decreases gradually. The diameter increased first and then decreased. When the molar ratio was 5:5, the optical band gap value was close to 3.2 EV, and the diameter and height of the nanoscale increased gradually with the increase of the concentration of the precursor solution, and the transmittance decreased gradually. When the concentration of precursor solution is 50 mm and 75 mm, the ZnO nanoarray changes from six prism needle shape to conical shape, and the diameter and height increase gradually and the transmittance decreases when the reaction temperature increases. When the molar ratio of Zn2 / HMTA was 5: 5, the concentration of precursor solution was 25 mm, and the reaction temperature increased to 90 鈩，

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