磁性半导体纳米晶的碳纳米管模板构筑及吸附-可见光催化降解有机污染物研究

It is significantly important from the viewpoints of theory and application to develop and explore magnetically separable nanophotocatalysts activated by visible light for solving environment pollution and energy shortage. This study is aimed to design and synthesize series of magnetic semiconductor nanocrystals templated by carbon nanotubes with excellent adsorption properties, visible-light photocatalytic activities and convenient recovery. Their photocatalytic activities will be investigated by photocatalytic degradation of organic pollutants under visible light irradiation.Then the synergistic effect and degradation mechanism of adsorption, visible light photocatalytic degradation of organic wastewater on the novel carbon nanotube-templated magnetic semiconductor nanocrystals will be revealed. The study will provide not only a new thought and scientific basis for the preparation of the carbon nanotube-templated magnetically semiconductor nanocrystals, but also an environmentally friendly wastewater treatment technique by simplifing the process and reducing the operation cost. Moreover, it is of academic importance to promote the overlapping between corresponding disciplines including environment, chemistry, energy, material and etc.

研制和开发新型磁分离型太阳光驱动纳米光催化材料对解决环境污染和能源短缺具有重要的科学意义和实用价值。本项目旨在利用碳纳米管为模板设计合成具有良好吸附-可见光催化性能且易回收的磁性半导体纳米晶复合光催化材料，研究其可见光催化降解有毒有机污染物的催化活性，揭示其吸附-光催化-磁回收处理有机废水机理。该集成式磁性半导体纳米晶复合材料的研究与开发，不仅为制备新型磁性可见光催化材料提供崭新的思路和科学依据，简化有毒有机污染物废水的处理工艺，降低深度水处理成本，同时也可促进环境、化学、能源和材料等学科的交叉融合，有着重要的学术意义。

为了解决现有环境光催化剂存在的吸附性差、光催化活性低以及催化剂回收难等主要缺点，我们对磁性半导体纳米晶的碳纳米管模板构筑及吸附-可见光催化降解有机污染物进行了深入地研究。首先，利用碳纳米管为模板设计合成系列具有良好吸附-可见光催化性能且易回收的磁性半导体纳米晶复合光催化材料。其次，我们研究发现在碳纳米管上适量引用生物质（如壳聚糖、海藻酸）能提高磁性粒子的粘附作用；碳纳米管独特的结构及生物质分子链上的-NH2和-OH功能基团能提高材料对目标污染物的吸附性能；同时研究还进一步证实了碳纳米管能降低电子空穴对的复合几率，从而进一步提高材料的光催化氧化降解效果。再次，模型污染物的初始浓度、pH值、催化剂投加量等操作因素对复合材料处理有机污染物效果有显著影响，且光催化降解过程均符合假一级反应动力学模型。最后，在本项目的资助下(No. 51208331)，发表磁性半导体纳米晶制备、表征和吸附-可见光催化降解有机污染物论文10篇(其中SCI源刊论文9篇，发表期刊影响因子大于2的论文7篇)，申请国家发明专利3项(已授权2项)。这些研究为磁性半导体纳米晶在吸附和光降解有机污染物中的应用提供了理论依据和指导。