Nanotechnology, or molecular-scale engineering, is no longer the stuff of science fiction but is producing a slew of practical, real-world applications.
As my colleague
this week, it is nanotechnology that holds the key to reducing the cost of producing fresh water in the parched Arabian peninsula and to making solar energy an economically viable power source for driving the process.
"The culmination of our joint research initiatives has enable us to radically reduce the cost of water through the development of nanotchnologies that revolutionise traditional desalination methods and renewable energy sources," said Takreem el Tohamy, the IBM general manager in the MENA region, describing the potential of a collaboration with Saudi Arabia's
(KACST) to build a
But what exactly has nanotechnology achieved and what is its potential for improving processes for removing salt from water and harvesting sunlight?
The following rundown merely scratches the surface of at least three decades of research, but it strives to untangle some of the microscopic threads that nanoscientists are following.
For more detail on the Saudi project, visit the
, posted on the
Hamm describes how nanotechnology has helped make better membranes for "reverse osmosis", the more modern of the two main commercial processes so far developed for water desalination.
Reverse osmosis was developed in the 1980s, which was also when nanotechnology got started. But the membranes that act as microscopic filters to draw salt out of water have never been problem free. They wear out too quickly as chlorine breaks down their molecular structure and their pores become clogged with organic debris and microbes. The researchers at KACST have succeeded in producing membranes that are resistant to chlorine and fouling, so they do their job better for longer, lowering desalination costs.
Another potential breakthrough in water treatment was recently reported by
Scientists at the
(MIT) and in Korea have developed a
to desalination using silicone-based nanotechnology that could led to the development of portable desalination units that could be powered by solar cells or batteries. The units could deliver enough fresh, sanitised water to supply the needs of a family, small village or a work crew in a remote location.
On the solar front, the
how nanotechnology is making it possible to develop highly efficient materials that can capture more energy with less. Using less of exotic materials reduces costs, as do ultra-thin-film solar panels that can be printed onto low-cost backing materials.
Enterprising scientists have even developed "nano-antennas" that can be etched onto silicon wafers to collect infrared radiation after dark.
Last but not least - well, maybe approaching least - an
website describes how another group of MIT researchers are bioengineering viruses to act as scaffolds for nanoscale components for splitting water molecules into hydrogen and oxygen. The two required molecular components are iridium oxide, a catalyst, and a biological pigment, zinc porphyrin, that absorbs light to power the reaction in the same way as the chlorophyll that makes leaves green.
The research could lead to a more energy efficient way to produce hydrogen from water than by zaping it with electricity. In the future, that could lead to a cost-efficient process for solar-powered production of carbon-free fuel.