Book excerpt: Delving into the development of plasmonic nanosensors to detect toxic heavy metal ions in aqueous media, this book explores a significant and burgeoning branch of nanosensor technology based on plasmon resonance and serves as a guide for conducting research in this area. All types of nanosensors for water treatment and detection of heavy metals are also introduced. Plasmonic Nanosensors for Detection of Aqueous Toxic Metals provides up-to-date data upon which researchers and ecologists, industrialists, and academicians can build to create a variety of plasmonic nanosensors. This book also covers paper-based devices based on plasmon for quantifying toxic metals in water and considers important applications of different plasmon-based nanomaterials—graphene, core-shell, quantum dots, nanoporous membrane, carbon nanotubes, and nanofibers. It is an accessible resource for all those involved in the field of nanosensors and their applications and can pave the way for a better understanding of nanosensor technology with regard to toxic metals. Key features: Gives an in-depth account of the extraordinary optical property at the nanoscale and its use in sensing Offers up-to-date study and practical results for academia, researchers, and engineers working in water treatment and purification Provides sensing application of thematic nanomaterials such as quantum dots and core-shell