Energy and Environment

In the field of energy, nanotechnology is being used to reduce the cost of catalysts used in fuel cells to produce hydrogen ions from fuel such as methanol and to improve the efficiency of membranes used in fuel cells to separate hydrogen ions from other gases such as oxygen.
Nanoparticles are also useful in the manufacture of solar cells by reducing manufacturing costs (need lower process temperature instead the high temperature vacuum deposition) and installation costs by producing flexible rolls (instead crystalline panels).
Regarding batteries, nanotechnology could offer some advantages: to reduce the possibility of catching fire by providing less flammable electrode material, to increase the available power and decreasing the required recharge  time by coating the surface of an electrode with nanoparticles, and to increase the shelf life using nanomaterials to separate liquids in the battery from solid electrodes.
Moreover, the shortage of fossil fuels such as diesel and gasoline can be addressed by making the production of fuels from low grade raw materials cheaper, increasing the mileage of engines, and making the production of fuels from normal raw materials more efficient.
It is also possible to increase the electricity generated by windmills using epoxy containing carbon nanotubes. The resulting blades are stronger and of lower weight, and therefore the amount of electricity generated by each windmill is greater.
Nanotechnology also has the potential to revolutionize the agri-food industry with novel tools for molecular management and rapid disease detection, improving plants' ability to absorb nutrients, controlling insects with the use of bio-pesticides, and monitoring conditions environmental conditions of the plant. Researchers are working in the use, for instance, of microsensors made from silica and carbon to monitor the presence of pathogens.
Another well-known use of nanotechnology is wastewater treatment. One challenge is the removal of industrial water pollution. Nanoparticles can be used to convert the contaminating chemical in underground ponds through a chemical reaction to make it harmless. Another challenge is the removal of salt or metals from water by a deionization method using electrodes composed of nano-sized fibers, or improve the filtration of virus cells using nanostructured catalytic membranes. Therefore, due to their unique activity toward recalcitrant contaminants and application flexibility, nanomaterials offer the potential for treatment of surface water, groundwater and wastewater contaminated by toxic metal ions, organic and inorganic solutes, and microorganisms.
Nanostructured membranes are also used from industrial plant exhaust streams to improve air quality, and catalysts serve to reduce air pollution. For instance, researchers have demonstrated a catalyst, in which gold nanoparticles have been embedded, that breaks down VOCs at room temperature.