This book brings together multiple aspects of the recent research conducted in the field of nanotechnology covering topics such as the synthesis of various nanoparticles, nanorods, graphene, graphene oxide-metal composites, characterization of these materials, and ample aspects of various applications including in heavy metal sensing, optoelectronic devices, gas sensing, solar cells, biomedical sensors, role in the drug delivery, and waste-water treatment. The book is of interest to early career researchers, who are trying to grasp multiple aspects of nanomaterials and nanocomposite synthesis and its potential applications.