The design, characterisation, production and application of structures, devices and systems by controlling shape and size at the nanoscale. The father of nanotechnology is physicist Richard Feynman. Nano-science and nanotechnology are the study and application of extremely small things, and they can be applied in any other science subject, including chemistry, biology, physics, materials science, and engineering.
Materials with unusual physical, chemical, and biological properties can arise at the nanoscale. These properties can differ significantly from those of bulk materials and single atoms or molecules. With nano ingredients, the physical characteristics of materials frequently alter substantially. Composites produced from nano-sized ceramics or metals with particle sizes less than 100 nanometers can become significantly stronger than predicted by present materials-science models. Metals with a grain size of roughly 10 nanometers, for example, are up to seven times harder and tougher than their ordinary counterparts with grain sizes in the hundreds of nanometers. The crazy world of quantum physics is to blame for these abrupt alterations. The bulk characteristics of any substance are just the average of all quantum forces acting on all atoms. As you get smaller and smaller, averaging stops working.
Materials' characteristics might differ at the nanoscale for two basic reasons:
Surface Area
First, when compared to the same mass of material generated in a bigger form, nanoparticles have a considerably greater surface area. This can cause materials to become more chemically reactive (in some circumstances, materials that are inert in their larger form become reactive when generated at the nanoscale level), as well as change their strength or electrical properties.
Quantum Size Effects
Second, quantum effects can begin to dominate matter's behaviour at the nanoscale, particularly at the lower end, influencing optical, electrical, and magnetic properties. This phenomenon covers the physics of electron characteristics in solids with large particle size reductions. Going from macro to micro dimensions has no influence on this effect. When the nanoscale size range is reached, it becomes dominating.