Nanomaterials Applications for Environmental Matrices - Chapter 4 - Microbe Decontamination of Water

The United Nations expects that one quarter of the world’s population will face water shortages by 2050. Expanding population and climate change have collaborated to increase water stress in many parts of the globe that are already suffering from substantial water scarcity. Along with a lack of political initiatives and infrastructure, drought, irrational use of water resources, and the contamination of groundwater and fresh surface water are reasons why clean water is becoming a precious commodity. Contaminants, such as heavy metals, hormones, and pathogenic microorganisms, enter water supplies through the deliberate disposal of municipal, industrial, and agricultural wastes. Particularly, the consumption of water contaminated with pathogenic microbes poses a great threat to humans and animals. Conventional approaches for water disinfection consist of the use of free chlorine, ozone, and UV-irradiation. However, conventional technologies, such as chlorination, are often risky due to the production of toxic byproducts or can be costly as in the case of UV-radiation exposure. To address this challenge, materials science, through the development of antimicrobial nanomaterials, has provided alternative solutions to the problem of water disinfection and treatment. The objective here is to offer a systematic, concise, and comprehensive overview of the development of nanomaterials for water disinfection, and their advantages, limitations, and future perspectives. Herein, the discussion will be focused on carbon nanomaterials (graphene-based materials, carbon nanotubes, and fullerenes), metallic nanoparticles, photocatalytic particles, and hybrid materials.