Nanotechnology or Nanoscience is the science of the extremely small – objects smaller than 100 nanometres (0.00001 cm). At these scales, the properties of materials change dramatically. Factors such as Brownian motion, surface stickiness and quantum effects become important.
Nanotechnologies are based on a range of new materials, including carbon C60, carbon nanotubes, nanoparticles, nanowires, and polymers based on nano-size subunits.
A huge range of applications are possible, based on stronger, lighter or smaller materials, or compounds with unusual optical or electrical properties.
Early applications are enhancing existing products – tennis racquets, golf clubs, and sunscreens. Possible medical applications include better implants, wound dressings, diagnostics and cancer treatments.
Combining biological molecules with nanomechanical components is creating radically new materials; these are at an early stage of development.
The public currently has little input into policy making in science and technology. Environmental concerns focus mainly on nanoparticles but very little is known about their impact on living things.
Nanotechnologies could increase the divide between rich and poor, but could also provide products useful to the developing world and may be easier for poorer countries to take up.
Dye-sensitized solar cells (DSSCs) based on nanocrystalline titanium dioxide (TiO2) thin films are built using a process called microfabrication based on nanotechnology.
These solar cells have reported solar-to-electric energy conversion efficiencies of greater than 10%. Given the low cost of their components and their demonstrated conversion efficiencies, DSSCs show true promise for being an inexpensive, renewable, and environmentally benign alternative to fossil fuels.
Here is a guide by a 7th Grader (Maria Andreina Murillo) on how to create a solar cell by microfabrication using nanomaterials.