高活性｛111｝面暴露的锐钛矿二氧化钛的制备及其光催化性能的研究
发布时间：2018-07-18 09:22
【摘要】：TiO2的表面形貌对于其光催化性能有着至关重要的影响。本研究中,我们通过水热合成法制备了一种新型的锐钛矿纳米二氧化钛,在NH4F和HF的作用下,高活性{111}面占主导地位。本研究的主要进展通过调节NH4+和F-的摩尔比例,可以直接控制二氧化钛暴露的晶面。当NH4+和F-的摩尔比达到1:2,能够得到{111}面为主要暴露面的锐钛矿二氧化钛。当只加入氨水或HF时,得到的纳米锐钛矿二氧化钛暴露面分别为{101}面或{001}面。这样的{111}面暴露的纳米二氧化钛显示出优异的光催化活性,这种活性是{001}面的片状二氧化钛和商用的德固赛P25的2-3倍,也就证实了{111}面比{001}和{101}面具有更高的光催化活性。原子在的表面是不饱和Ti5c、Ti3c和O2c模式产生更高的吸附和降解能力。同时,我们还研究了用这种方法所制备的不同晶面暴露的纳米锐钛矿二氧化钛的光催化选择性能。通过上述水热合成法得到{101}面、{111}面和{001}面为主要暴露面的锐钛矿二氧化钛后,煅烧去除表面吸附的原子。结果显示,{101}面暴露的二氧化钛结合有残留的N,并且以不饱和N3c的模式存在,在对MO和MB的混合溶液进行光催化选择性实验中表现出对MO的选择性降解。而{111}面和{001}面暴露的锐钛矿二氧化钛表现出对MB的光催化选择性。这证明了光催化选择性可以被不同的主导晶面影响。经过进一步的分析,我们得出{001}面和{111}面表面上存在不饱和的O2c,这样的结合模式提高了吸附选择性,在光催化选择实验中表现出的对MB的选择性。在{111}表面上,存在的都是不饱和O2c,这也导致{111}面更好的光催化选择性。我们的研究提供了一种通过水热法进一步探索纳米材料制备的方法,同时希望发展一个新的光催化选择的方式,提供一种更深层次的对不同晶面的二氧化钛的理解。并且,这项研究的结果也可以应用在光催化、太阳能蓄电池和传感器等领域。
[Abstract]:The surface morphology of TiO2 plays an important role in the photocatalytic performance. In this study, we prepared a new anatase nano-TiO _ 2 by hydrothermal synthesis. Under the action of NH _ 4F and HF, the highly active {111} surface dominated. By adjusting the molar ratio of NH _ 4 and F _ -, the crystal faces of TIO _ 2 exposed can be directly controlled. When the molar ratio of NH4 to F- reaches 1: 2, anatase TIO _ 2 with {111} plane as the main exposed surface can be obtained. When only ammonia or HF was added, the exposed surfaces of anatase were {101} and {001}, respectively. The nanometer TIO _ 2 exposed to the {111} surface shows excellent photocatalytic activity, which is 2-3 times higher than that of the {001} flake titanium dioxide and the commercial Degussi P25. It is also confirmed that the {111} face has higher photocatalytic activity than the {001} and {101} masks. On the surface of the atoms, the unsaturated Ti5cTi3c and O2c modes produce higher adsorption and degradation ability. At the same time, we also studied the photocatalytic selectivity of nanocrystalline anatase TIO _ 2 prepared by this method. Anatase TIO _ 2 with {101}, {111} and {001} faces as main exposed surfaces was obtained by hydrothermal synthesis, and the atoms adsorbed on the surface were removed by calcination. The results show that titanium dioxide exposed to {101} surface binds with residual N, and exists in the mode of unsaturated N3c. The selective degradation of MO in the mixed solution of MO and MB is demonstrated in the photocatalytic selectivity experiment. The anatase exposed to {111} and {001} surfaces showed photocatalytic selectivity to MB. It is proved that the photocatalytic selectivity can be affected by different dominant crystal planes. After further analysis, we found that there are unsaturated O _ 2C on the {001} and {111} surfaces, which enhances the adsorption selectivity and exhibits the selectivity to MB in the photocatalytic selection experiment. On the {111} surface, unsaturated O _ 2C exists, which also leads to better photocatalytic selectivity on {111} surface. Our research provides a method for further exploring the preparation of nanomaterials by hydrothermal method. At the same time, we hope to develop a new way of photocatalytic selection and provide a deeper understanding of titanium dioxide with different crystal faces. The results can also be used in photocatalysis, solar batteries and sensors.
【学位授予单位】：杭州电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ134.11;O643.36
本文编号：2131467
[Abstract]:The surface morphology of TiO2 plays an important role in the photocatalytic performance. In this study, we prepared a new anatase nano-TiO _ 2 by hydrothermal synthesis. Under the action of NH _ 4F and HF, the highly active {111} surface dominated. By adjusting the molar ratio of NH _ 4 and F _ -, the crystal faces of TIO _ 2 exposed can be directly controlled. When the molar ratio of NH4 to F- reaches 1: 2, anatase TIO _ 2 with {111} plane as the main exposed surface can be obtained. When only ammonia or HF was added, the exposed surfaces of anatase were {101} and {001}, respectively. The nanometer TIO _ 2 exposed to the {111} surface shows excellent photocatalytic activity, which is 2-3 times higher than that of the {001} flake titanium dioxide and the commercial Degussi P25. It is also confirmed that the {111} face has higher photocatalytic activity than the {001} and {101} masks. On the surface of the atoms, the unsaturated Ti5cTi3c and O2c modes produce higher adsorption and degradation ability. At the same time, we also studied the photocatalytic selectivity of nanocrystalline anatase TIO _ 2 prepared by this method. Anatase TIO _ 2 with {101}, {111} and {001} faces as main exposed surfaces was obtained by hydrothermal synthesis, and the atoms adsorbed on the surface were removed by calcination. The results show that titanium dioxide exposed to {101} surface binds with residual N, and exists in the mode of unsaturated N3c. The selective degradation of MO in the mixed solution of MO and MB is demonstrated in the photocatalytic selectivity experiment. The anatase exposed to {111} and {001} surfaces showed photocatalytic selectivity to MB. It is proved that the photocatalytic selectivity can be affected by different dominant crystal planes. After further analysis, we found that there are unsaturated O _ 2C on the {001} and {111} surfaces, which enhances the adsorption selectivity and exhibits the selectivity to MB in the photocatalytic selection experiment. On the {111} surface, unsaturated O _ 2C exists, which also leads to better photocatalytic selectivity on {111} surface. Our research provides a method for further exploring the preparation of nanomaterials by hydrothermal method. At the same time, we hope to develop a new way of photocatalytic selection and provide a deeper understanding of titanium dioxide with different crystal faces. The results can also be used in photocatalysis, solar batteries and sensors.
【学位授予单位】：杭州电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ134.11;O643.36
【共引文献】
相关期刊论文 前1条
1 何琴;黄保军;李颖颖;法文君;;生物模板法制备微纳米二氧化锡[J];化工新型材料;2012年05期
相关硕士学位论文 前2条
1 满丽莹;微波溶剂热制备纳米结构SnO_2及其气敏性研究[D];济南大学;2012年
2 韩丽仙;锡基微纳米晶体的制备及其性能的研究[D];上海师范大学;2013年
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