石墨烯基吸附剂的设计及其对水中抗生素的去除

抗生素的大量使用,所带来的环境污染问题受到广泛关注。吸附法因去除效率高、普遍适用性强,呈现出广阔的应用前景,开发新型吸附剂是高效能吸附处理的关键。近年来石墨烯优良的物理和化学性质以及吸附性能,使其成为重要的抗生素吸附剂。由于石墨烯自身的局限性以及对石墨烯吸附剂处理效能和稳定性的要求,基于石墨烯设计开发了多种石墨烯基吸附材料。而目前基于水体中抗生素的石墨烯基复合材料的设计、合成及其吸附作用机制缺乏相关的系统性综述。本文综述了目前水体中抗生素的危害,针对石墨烯基复合吸附材料中,广泛关注的磁性石墨烯吸附剂、聚合物/石墨烯吸附剂、三维石墨烯凝胶和石墨烯/生物炭吸附剂的设计和制备方法进行了总结和概述,并阐述了石墨烯基吸附材料对水体中抗生素的主要吸附作用机制。最后,本文对石墨烯基吸附材料去除水体中抗生素未来的发展方向进行了展望。

Design of Graphene-based Adsorbents and Its Removal of Antibiotics in Aqueous Solution

It is a widespread concern that the extensive use of antibiotics has caused not only harm to the human body but also heavy environmental pollution. Because of its high efficiency and universal applicability, adsorption technology has significant application potential for the removal of antibiotics. The development of new adsorbents is critical for high-efficiency adsorption treatment. In recent years, the excellent physical, chemical, and adsorption properties of graphene have made it an important antibiotic adsorbent. The high specific surface area and large number of pores of graphene provide many adsorption sites for antibiotics. In addition, the conjugated structure makes graphene relatively electronegative, which also affects adsorption. Due to the limitations of graphene and the increasing requirements for efficiency and stability of graphene adsorbents, a variety of graphene-based adsorbents have been developed to solve the issues of graphene agglomeration in aqueous solutions, poor graphene dispersibility, and poor adsorption performance. Thus far, there has not been a systematic review on the design, synthesis, and adsorption mechanism of graphene-based composites for the removal of antibiotics in aqueous solutions. The design and preparation methods for magnetic graphene adsorbents, polymer/graphene adsorbents, three-dimensional graphene gels, graphene/biochar adsorbents, and graphene-based adsorbents for catalytic degradation of antibiotics are also reviewed. We show the synthesis and design concepts of various graphene-based adsorbents, as well as their different physical and chemical properties and adsorption performance, so that we can distinguish and select different graphene-based adsorbents. We also discuss the design of adsorbents for different kinds of antibiotic contaminants to provide guidance to future researchers for choosing the appropriate design methods based on the antibiotic type. These graphene-based adsorbents can also be extended to the adsorption of various pollutants, which is of great significance for environmental protection. The main adsorption mechanism of antibiotics on graphene-based adsorbents in aqueous solutions is expounded. The cyclic structure of graphene determines the interaction between graphene and antibiotics, such as π–π and cation–π interactions. The numerous oxygen-containing functional groups on the surface of graphene oxide (GO) provide more possibilities for the design of graphene composites. Finally, the future development of graphene-based adsorbents for the removal of antibiotics in aqueous solutions is discussed. We recommend the design of highly-efficient, broad-spectrum, and selective adsorbents for high adsorption performance for multiple antibiotic contaminants in the environment. We also address the regeneration and disposal of graphene-based sorbents and promote green, harmless, and resource-based disposal.