Journal of Nanomaterials and Devices

Nanomaterials

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Nanomaterials are a class of material, where the each units have at least one dimension below 100 nanometers. They can be create of any element and are often classify into organic, inorganic, and hybrid materials.

Nanomaterials can form naturally, be made as by-products of combustion, or be deliberately engineered to carry out a specific function. These materials may show different physical and chemical properties compared to their bulk-form versions.

Nano-materials are often grouped based on how many of their dimensions are within the nanoscale. A nanoparticle is a type of nano-object that has all three dimensions within the nanoscale, with its longest and shortest sides being fairly similar in size. A nanofiber has two dimensions in the nanoscale, with nanotubes being hollow and nanorods being solid. A nanoplate or nanosheet has one dimension in the nanoscale, and if the other two dimensions differ greatly, it is called a nanoribbon. For nanofibers and nanoplates, the larger dimensions are not always confined to the nanoscale but are generally much larger—usually at least three times greater than the smaller dimensions.

Nanostructured materials are commonly classified according to the different phases of matter present within them. A nanocomposite is a solid material that contains at least one region, or set of regions, that is physically or chemically different from the rest of the material, with at least one dimension measuring in the nanometer range. A nanofoam, on the other hand, consists of either a liquid or solid substance that is filled with a gas, where one of the phases features structures or spaces that are nanoscale in size. A nanoporous material is a solid that contains nanopores, which are voids with open or closed pores at sub-micron sizes. A nanocrystalline material is made up of a significant number of crystal grains that are on the nanometer scale.

Nanomaterials are found in manufacturing, healthcare, and environmental areas. In healthcare, nanozymes act like enzymes for biosensing, imaging, and diagnosis. Nanostructured filters trap particles as small as viruses, and nanomaterial membranes assist in wastewater treatment. In air purification, nanotechnology was used to help manage MERS in Saudi hospitals. Nanomaterials improve insulation, lower friction in lubricants, and help repair worn parts. They also increase UV protection in sunscreen, give paints self-cleaning ability, and make sports equipment lighter. In the military, they improve camouflage. Nanomaterials also make catalytic converters more effective, cutting emissions and reducing the need for expensive metals like palladium and rhodium.