水热法合成锰、钛氧化物及其催化作用的研究

发布时间：2018-03-19 03:15

本文选题：锰氧化物　切入点：CO催化　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：在21世纪,环境治理和能源短缺逐渐成为人类共同面对的两大问题。煤、石油等化石燃料的不完全燃烧和工业废气的排放,容易造成大气的一氧化碳污染。并且由于化石燃料属于不可再生资源,如不开发其他资源而过分使用极易导致能源的枯竭。因此治理一氧化碳污染和开发可再生太阳能资源成为现今环境友好科学发展的重要方向。发展高效的一氧化碳氧化催化剂和可见光催化剂是目前科学研究的两个前沿方向。本文采用水热合成的方法,分别制备了锰氧化物和二氧化钛,并对其进行改性以增强催化效果。(1)水热法制备钙钛矿型的锰氧化物La_(0.5)Sr_(0.5)MnO_3,使用硝酸简单可控湿法刻蚀方法,选择性脱去La~(3+)和Sr~(2+)离子,得到高稳定性、保持钙钛矿形貌的新型类MnO_2锰氧化物(MO)。使用XRD、XPS、SEM、EDS、BET、H2-TPR等方法对其进行晶体结构、复合材料形貌、表面元素组成的进行了表征分析。新型锰氧化物MO具有较大的比表面积和优异的低温还原性能。通过CO氧化催化测试和活化能计算确定MO的催化氧化活性。结果表明这种酸处理方法,可以使锰氧化物的一氧化碳催化氧化性能得到显著的提高。(2)TiO_2具有抗光、抗化学腐蚀、价格低廉、制备简单的优点,而被广泛的应用在光催化领域。本文使用水热法在FTO导电玻璃上生长出TiO_2纳米线阵列,通过电喷雾电离(ESI)技术负载贵金属钯(Pd)纳米粒子对TiO_2纳米线阵列进行优化改性,得到复合材料:Pd/TiO_2纳米线阵列。通过X-射线光电子能谱(XPS)能够确定沉积的金属钯的价态为零,即Pd(0);在扫描电子显微镜(SEM)和透射电子显微镜(TEM)的观察下可知尺寸约为8 nm的Pd纳米粒子均匀地分散在TiO_2纳米线阵列上。通过光电流密度测试证实贵金属Pd负载的方法能够有效促进TiO_2纳米线阵列的光电流响应。
[Abstract]:In twenty-first Century, environmental protection and energy shortage has gradually become the two major problems facing mankind. Coal, oil and other fossil fuel incomplete combustion and industrial emissions of carbon monoxide, easy to cause air pollution. And because fossil fuels are non renewable resources, such as the exploitation of other resources and excessive use can easily lead to the depletion of energy carbon monoxide pollution. Therefore, governance and the development of renewable energy resources has become an important direction of the current environment of scientific development. The development of efficient carbon monoxide oxidation catalyst and visible light catalyst is the two science research at present. This paper uses the method of hydrothermal synthesis, respectively prepared manganese oxide and titanium dioxide, and its modification in order to enhance the catalytic effect. (1) manganese oxide La_ hydrothermal synthesis of perovskite type (0.5) Sr_ (0.5) MnO_3, using simple and controllable wet nitrate The etching method, selectively removing La~ (3+) and Sr~ (2+) ion, high stability, maintain the morphology of the new type of MnO_2 perovskite manganese oxide (MO). The use of XRD, XPS, SEM, EDS, BET, H2-TPR and other methods of crystal structure of the composite surface morphology, elemental composition was characterized. Analysis of new type manganese oxide MO with specific surface area and excellent low temperature reduction performance and more. Through the CO catalytic oxidation test and activation energy calculation to determine the catalytic activity of MO. The results show that the acid treatment method, can make the carbon monoxide catalytic performance of manganese oxide has been significantly improved. (2) TiO_2 with anti light. Corrosion resistant, low price, has the advantages of simple preparation, and is widely used in the field of photocatalysis. The hydrothermal growth of TiO_2 nanowire arrays on FTO conductive glass, by electrospray ionization (ESI) technology supported noble metal Palladium (Pd) nanoparticles were modified to optimize TiO_2 nanowire arrays, the composite material: Pd/TiO_2 nanowire arrays. By X- ray photoelectron spectroscopy (XPS) to determine the valence state of the deposited metal palladium is zero, namely Pd (0); in the scanning electron microscope (SEM) and transmission electron microscopy (TEM the size of the observation) was about 8 nm Pd nanoparticles were uniformly dispersed in TiO_2 nanowires array. The photocurrent density test confirmed that noble metal supported Pd can effectively promote the photocurrent response of TiO_2 nanowire arrays.

【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36

【相似文献】