碳纳米管/磷酸银新型复合光催化剂的制备及在可见光下降解抗生素类污染物的机理研究

Semiconductor photocatalysis is an efficient and energy-saving technique for degradation of antibiotics pollutes. Currently there exist problems in research field of photocatalytic degradation of antibiotics, such as low degradation efficiency under visible light irradiation, and lagged study on photocatalysis mechanism. Literature investigation results indicate that potential synergistic effect between CNTs and Ag3PO4 can enhance the efficiency of photocatalytic degradation of antibiotics. In order to solve the problems mentioned above, this project will excavate and utilize the synergistic effect between CNTs and Ag3PO4 in antibiotics degradation to obtain a novel CNTs/Ag3PO4 photocatalysts that can efficiently degrade antibiotics with solar energy, by exploring effective scheme of photocatalyst preparation to realize the close contact and optimal proportion of the two components. Thus, many advantages including strong absorption of visible light, high separation efficiency of photogenerated carriers, strong adsorption ability and high stability will be achieved simultaneously for the photocatalysts. Then, mechanism studies on the structure-activity relationship of the obtained photocatalysts will be carried out to ascertain the important factors influencing antibiotics degradation. This project aims at obtainment of a novel, efficient visible-light photocatalysts that can be used in antibiotics degradation, and also understanding of in-depth photocatalysis mechanism, hence providing guides for photocatalytic degradation research and control of antibiotics pollutes in future.

半导体光催化是一种高效、节能的抗生素类污染物降解技术。然而，在抗生素的光催化降解研究现状中仍存在可见光下降解效率不高、光催化作用机理研究滞后的问题。文献调研结果表明，碳纳米管（CNTs）与Ag3PO4之间具有潜在的可提高抗生素降解效率的协同效应。本项目针对上述问题，拟发掘和利用这种协同效应，探索有效的光催化剂制备方案来实现CNTs与Ag3PO4的紧密接触，以及二者之间的最佳比例，由此得到一种能利用可见光对抗生素进行高效降解的CNTs/Ag3PO4新型复合光催化剂，使光催化剂同时具有强的可见光吸收、高的光生载流子分离效率、强吸附能力、高稳定性等诸多优点。再以所得光催化剂为对象，进行光催化剂构效关系方面的机理研究，确定影响抗生素光催化降解的重要因素。本项目旨在获得一种能用于抗生素降解的新型、高效可见光催化剂，并深入认识其相关的光催化作用机理，为今后抗生素类污染物的光催化降解研究和治理提供借鉴。

在本项目资助下，以有机污染物的降解为主题，以提升催化剂的活性、稳定性和相关催化机理认识为目标，开展了一系列工作：首先，对BiVO4、Sb2S3经典光催化剂，采用一种简便的水热方法对其碳化，所得到的碳掺杂光催化剂降解有机染料污染物的活性高于纯BiVO4或Sb2S3。因元素掺杂提升经典光催化剂性能的空间有限，制备了HgO、HgI2等新型光催化剂。它们相对于经典的高活性光催化剂Ag3PO4，在染料降解中体现出更高的活性和稳定性。在研究有机染料光催化降解的同时，发现两种可光敏化降解染料的半导体AgIO4和Fe4I3O24H15，它们相对于光催化剂Ag3PO4，在光敏化降解染料时具有明显更高的活性或稳定性。最后，为突破污染物降解需要光照的局限，制备了两种可在无光照、室温条件下降解染料污染物的新型催化剂CeGeO4和Ce(IO3)4。此外，对污染物降解的相关催化机理进行了验证和解释。本项目研究结果对有机污染物的降解治理和新型、高效催化剂的制备具有借鉴意义。