Flexible, near-transparent, ultrathin material heralds revolution in e-readers, wearables and solar energy

A new material that is only a few atoms thick could one day be the staple of solar panels, e-readers and a host of wearable technology after researchers built a series of demonstration devices to prove its ability to harness or emit light.

The material, which is named tungsten diselenide, is one of a group of materials that are just one molecule thick. Following advancements in nanotechnology, scientists are racing to investigate the potential of these materials for use in electronic devices that source, detect and control light, known at optoelectronics.

The research, which was undertaken by scientists at Massachusetts Institute of Technology (MIT), involved using tungsten diselenide to create a working diode that could be used to make a variety of optoelectronic devices.

Although the diode was just a working prototype, Mitsui career development associate professor of physics Pablo Jarillo-Herrero, who oversaw the research, said that its properties were “very close to the ideal”.

The technology has enormous potential within optoelectronics. Perhaps most significant of these is the possibilities for photovoltaics.


The material could be used to make solar panels that were only millimetres thick, almost entirely transparent and very flexible. These could be used to turn almost any exterior surface into a solar panel – windows, walls and whole building facades could be wrapped in the material with minimal effect on appearance, potentially turning whole cities into massive solar power stations.

Buildings are not the only thing that this ultrathin solar panel could be attached to, however. The flexible nature of the material makes it suitable as part of clothing, meaning it could be worn by individuals and used to charge their smartphones, laptops and other devices.

The material’s other uses also lean towards wearables. One of the main uses is for LEDs, but with one advantage – unlike many other forms of LEDs, MIT says that “it should be possible to make LEDs that produce any colour”.

This could potentially make for a flexible surface with light patterns of video feeds that are tailored into clothing. It could also be idea for heads-up displays in cars and other vehicles, as well as for tables, kitchen worktops or other household services.

“The material could be used to make solar panels that were only millimetres thick, almost entirely transparent and very flexible.”

In an LED form the material could also be used to create an amazing e-reader – transparent and highly flexible but clearly displaying any content required.

The material can also be used to make photodetectors, or sensors that detect light. These are used across an enormous range of applications, from digital photography to medical devices. So if tungsten diselenide were to take off as a material, it could have wide-ranging impacts on many everyday gadgets and technologies.

The researchers also believe that the material could provide benefits in terms of speed and power consumption due to the material’s minute thickness.

Tungsten diselenide is made using selenium, a trace element that is found in metal sulfide ores, and which is a by-product of copper production.

If this material were to take off, selenium could – at least to some extent – replace silicon in electronic devices, which may pose a problem as there is less selenium on earth than there is silicon.

However, this may not be such a problem, as MIT postdoc Hugh Churchill explains: “It’s thousands or tens of thousands of times thinner [than conventional materials], so you’d use thousands of times less material to make devices of a given size.”

Body image courtesy of MIT.

On-the-go solar charging is coming to a street near you

It happens to all of us: you’re out and about and want to make a call when you realise that your phone is out of battery. Soon, however, this won’t be a problem – before long you could use Street Charge, a solar charging station designed to give you a burst of power while you’re out and about.

Street Charge is designed to give power to any electrical product with a USB connection, including tablets, cameras and mp3 players.

Each station features three micro USB connectors, which are commonly used in mobile phones and cameras, and three female USB connectors, which allow users to connect their own charging cables to the unit.

Street Charge solar charging

Launched in London, UK, yesterday by European suppliers Environmental Street Furniture, Street Charge features three 20 watt solar panels that power up an internal battery, meaning it can be used both during the day and at night.

It also means that Street Charge will work regardless of the weather – a vital feature in rainy countries such as the UK.

The charging station can be installed anywhere outside, and is particularly suited to green spaces, bus and rail stations and universities.

Street Charge also proved its value for public events at San Diego Comic-Con in July. Charging units set up for the event were very positively received by attendees and journalists alike, so we could see the station become a stable of festivals and large events around the world.

Street Charge solar charging

Street Charge was originally launched in the US back in June 2013. The first units were located in New York City, and there are now 25 across all five boroughs.

In the eight months Street Charge has been available for, the unit has spread across the US. There are now over 100 charging stations across several states, including Texas, Florida and California.

However the UK launch is one of the first times Street Charge has made it worldwide, with only a handful of places having already had units installed. The only places with Street Charge already in place are Amsterdam, the Netherlands; Dubai; Lima, Peru and Sydney, Australia

Street Charge might be effective, but as something located in public spaces it has to be highly robust to avoid damage from vandalism. The cords are covered with reinforced, industrial-grade material to make then highly resistant to abuse, and the tips are nickel and gold plated for extra durability.

Even if a cable were to be irreparably damaged, it is designed to be easily replaced, giving the station the best chance of surviving anything the public can throw at it.

All of this may be unnecessary, however. Environmental Street Furniture managing director Alan Lowry said that the company had any serious issues with sabotage or vandalism. “We thought that would be an issue in New York, but we didn’t see it,” he said.

Images courtesy of Street Charge.