Carbon Dots and Other Nanomaterials for Advanced Water Quality Monitoring

The monitoring of water quality is vital in the assurance of safe drinking water and environmental sustainability. The conventional methods, while effective, are usually constrained by their sensitivity, cost, and time-consuming laboratory procedures. The solution to these challenges has come in the form of nanotechnology, with carbon-based nanomaterials (carbon dots (CDs) and other nanomaterials) playing one of the transformative roles in nanotechnology. The CDs, with their spectacular optical characteristics, biocompatibility, and low cost of production, are highly sensitive, quick, and economical techniques for detecting most of the waterborne agents such as heavy metals, organic silvers, and bacterial pathogens. This chapter details the synthesis, optical characteristics, and sensing principle of CDs and their prospects in water quality monitoring. It also looks at the incorporation of other nanomaterials, including metal nanoparticles, quantum dots, graphene, and metal oxides, and explores their complementary applications in boosting detection sensitivity, selectivity, and multifunctionality. By thoroughly discussing these nanomaterials, their applications, and the trend in the current research, this chapter gives a detailed overview of how they will be used to improve the water quality testing in the future. The possibility of these nanomaterials to offer real-time, portable, and precise monitoring systems is indeed a radical step toward protecting water resources and human health.