Identification and removal of nano-/micro-plastics using nanostructured materials: from fundamentals to environmental applications

Abstract

The rising issue of microplastic (1 μm–5 mm) and nanoplastic (<1 μm) pollution in the environment due to urbanization, industrialization, and modernization of society poses serious health and environmental risks. These nano-/micro-plastic (NMP) contaminants infiltrate air, water, and soil systems, threatening the ecological balance and food safety through their persistence and toxicity. Consequently, extensive research efforts have been devoted to developing sensitive detection and efficient removal strategies for NMPs at trace levels. Interestingly, due to the advancements in nanoscience and the development of various nanostructured materials (i.e., 0D–3D nanomaterials) with excellent surface and optoelectronic properties, several promising strategies have been developed for the ultra-detection of NMPs and their removal from the environment (including air, water, and soil). Such nanostructured materials have been explored in recent years as a next-generation solution for environmental monitoring and remediation of NMPs. This review comprehensively discusses various nanostructured materials, including plasmonic metals, semiconductor photocatalysts, 2D nanomaterials, and 3D frameworks, such as MOFs, along with their hybrids, emphasizing their unique structural and functional attributes that enable effective sensing, identification, and removal of NMPs from the environment. The present review also highlights the sources, characteristics, and impacts of NMPs and discusses conventional detection and removal methods. The emerging use of nanostructured materials in SERS and electrochemical sensing is then discussed, together with NPS removal through adsorption and photocatalytic processes. While such nanomaterial-based methods demonstrate superior efficiency and selectivity compared to the conventional methods, their practical application is constrained by their cost, synthesis complexity, and scalability limitations. Finally, various challenges, including laboratory performance and the environmental implications and related risks, are discussed.