A nanostructured coating that can be applied to almost any fabric makes cloth strongly repel water, even remaining dry after two months underwater (Image: University of Zurich/Wiley Vch) A close of up the structures on a gecko’s foot, compared with the nanotubes that make up a synthetic mimic that is even stickier than the real thing (Image: Science) This “nanotech tissue” is made from a tangled mix of manganese oxide nanowires. It strongly repels water, but it will absorb 20 times its own weight in engine oil (Image: Nature)


When you get down to scales of a billionth of a metre, even the simplest, best-known materials can take on surprising new properties. Strength, adhesion and absorption can all be multiplied manyfold if you just find the right nanoscale structure. And, in 2008, many engineers did.

Tangled manganese-oxide nanowires were shaped into a kind of paper tissue that guzzles up oil spills without absorbing a drop of water. While a different nano-textured pattern that can be applied to any fabric proved able to make cloth unwettable, even emerging dry after two months underwater (see image, right).

A material that mimics nanostructures found on that marvel of stickiness – a gecko’s foot – is so successful it is up to 10 times as adhesive as the real thing. See an image of the material side by side with a real gecko’s foot.

Energy answers

Novel nanotech ideas were also harnessed in the search for alternatives to existing energy sources in 2008.

A novel mixture of gold-filled carbon nanotubes and lithium hydride proved capable of converting radiation directly into electricity and may provide a new way to power spacecraft with long missions.

Carbon nanotubes were also part of a plan to create a new kind of artificial photosynthesis. The tubes act as a temporary store for electrons harvested from light by dye molecules, before the electrons are used to drive chemical reactions that remove CO 2 from the atmosphere.

It could even be possible to transform the greenhouse gas into fuel.

Turning to more established green technologies, the hunt for a better battery to unlock the potential of electric cars also depends on nanoscale advances, that pack more powerful chemistry into a smaller volume.

Electric appeal

Silicon chip designers have been venturing into the nanoscale for years – the latest chips have features as small as 45 nanometres. But as silicon comes close to being unable to shrink further, nanocomponents could offer improved performance at similar scales.

A material called graphene – a sheet of carbon just a single atom thick – is one contender. This year it was discovered to be capable of smashing the conductivity record for a material at room temperature, something that sets a speed limit on computation.

Borrowing one of nature’s nanostructures – DNA fibres which measure just 2 nm across – to create a kind of tiny fibre-optic cable could provide a way to connect up the components of future computers that send data with light not electricity.

Safety controls

But nanotechnology is not just about neat new discoveries. Just as when any exotic new class of materials comes along, the safety of nanomaterials must be assessed.

The extent to which we have already started releasing nanoparticles into the environment is essentially unknown, but the process is certainly under way. The silver nanoparticles commonly added to clothing such as socks to kill off bacteria were found to easily leak into waste water during washing. There are likely more findings like this to come. Some everyday products like cleaners and sun cream already contain nanoparticles, and nanoscale structures are increasingly used in industry.

Lab-based investigations of the health effects of nanoparticles also produced worrying results. One study found that mice that inhaled nanotubes suffered effects similar to those caused by asbestos. Another showed that earthworms that eat nanotubes suffer a reduced reproductive rate.

Yet very few such studies have taken place, leading the UK’s Royal Commission on Environmental Pollution to declare that “urgent” work is needed to asses the effects of nanoscale objects on health and the environment.

However, defaulting to a position of declaring all artificial nanostructures bad is not the answer. Nature works on the nanoscale too, and as our editorial pointed out there’s no reason to assume that man-made nanoparticles are automatically better or worse than the many natural ones.