Nanostructures are engineered structures with features at the nanoscale generally refer to the material systems that are in the range of 1 to 100 nanometers. In a nanostructure, electrons are normally confined in one of the dimensions, whereas in the other dimensions, they are free to move in all directions. These nanomaterials have enormous applications in electronics, medicine, agriculture, biomedical engineering, and environmental remediation techniques, which make these materials among the most promising and evolving materials in the recent era. Nanostructured materials can be categorized into four types such as: (1) inorganic-based nanomaterials; (2) carbon-based nanomaterials; (3) organic-based nanomaterials; and (4) composite-based nanomaterials. Generally, inorganic-based nanomaterials include different metal and metal oxide nanomaterials. Carbon-based nanomaterials include graphene, fullerene, single-walled carbon nanotube, multiwalled carbon nanotube, carbon fiber, an activated carbon, and carbon black. The organic-based nanomaterials are formed from organic materials excluding carbon materials, for instance, dendrimers, cyclodextrin, liposome, and micelle. The composite nanomaterials are any combination of metal-based, metal oxide-based, carbon-based, and/or organic-based nanomaterials, and these nanomaterials have complicated structures like a metal-organic framework.