From the Ages of Stone, Bronze and Iron, to the advent of steel,
plastics and semiconductors, the history of civilization has often been
written in our increasingly sophisticated mastery of new substances and
compounds.
The 20th century witnessed an explosion in the development
of synthetic materials, as well as the creation of new combinations
of materials to achieve desired physical effects. Now chemists,
physicists and engineers are poised to produce a whole new
generation of novel materials with specifically tailored
properties, some of which would have seemed like science
fiction only a few years ago. NSF supports a wide variety
of programs in that ongoing effort.
One of the most exciting is the race to devise superconducting
materials -- those with no resistance to electrical
current -- that can operate at ever-higher temperatures.
Existing superconductors must be cooled by liquid nitrogen
or liquid helium, making them impractical for large-scale
operations. Superconductors that operate at or near room
temperature could transform global use of electrical power.
At the same time, numerous investigators are trying to find
more efficient and inexpensive materials for photovoltaic
devices that convert the energy of sunlight to electricity.
Substantial advances in this area could drastically reduce
humanity’s demand for fossil fuels to generate electricity.
Materials researchers are also intensely interested in ways
to control the optical properties of different substances.
Some are working on light-emitting diodes (LEDs, best known
as the glowing red or green lights on electronic appliances)
that could produce white light for general illumination.
Others are engineering new kinds of liquid crystals -- akin
to those used in laptop computer screens -- that can
work in a host of applications, from windows with variable,
user-controlled transparency to tiny sensors that change
color with temperature. Still others are devising new ways
to control the passage of light signals through fiber-optic
cables and switches in order to speed and improve communication.
In medicine and physiology, potential uses for new materials
are nearly endless, including substances that can serve as
synthetic frameworks for bone growth, forms of artificial
skin and joints, implantable drug-delivery systems, "bio-compatible" materials
that do not trigger immune-system rejection and engineered
materials that can carry out the function of organs.
That field benefits from parallel research into "smart" materials
that are designed to react to changes in their environment.
Some can sense motion and counter it, thus damping vibration.
Others change shape or viscosity in response to stress, temperature
or electrical activity, but "remember" their original
configurations. Many smart materials will be employed in creating
the coming generation of compact, low-power sensors that can
detect toxic chemicals, bio-hazards or radiation, as well as
dozens of other stimuli.
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