Tag Archives: led

A brief word on a new supermaterial

graphene-transistorGraphene: a material consisting of a sheet of carbon atoms one atom thick. Graphene was first identified only a few years ago, and has since been proferred for all sorts of uses, including ultracapacitors, spintronics, and now as a light source:

Microchips is just one of the material’s potential applications. Because of its single-atom thickness, pure graphene is transparent, and can be used to make transparent electrodes for light-based applications such as light-emitting diodes (LEDs) or improved solar cells.

It is also apparently very strong:

The mobility of electrons in graphene — a measure of how easily electrons can flow within it — is by far the highest of any known material. So is its strength, which is, pound for pound, 200 times that of steel.

The problem is to find a way to mass-manufacture it:

The trick that enabled the first demonstrations of the existence of graphene as a real separate material came when researchers at the University of Manchester applied sticky tape to a block of graphite and then carefully peeled off tiny fragments of graphene and placed them on the smooth surface of another material.

“They don’t care if they go to a lot of effort to make five tiny pieces, they can study those for years.” But when it comes to possible commercial applications, it’s essential to find ways of producing the material in greater quantities.

[from Physorg][image from Physorg]

The little house that could

The house's heating water tank

Built for just £210,000, Michael and Dorothy Rea’s house on Britain’s northernmost inhabited island is amongst the most efficient in the world. Boosted by the strong winds surrounding the island of Unst, the house has its heating and power, plus an electric car and substantial greenhouse, entirely powered by renewable sources.

The house reminds me a little of the building in Susan Palwick’s ‘Shelter’ with its smart uses of technology. The house takes heat from the air around it and stores it in a water ‘battery’ to heat the home. The greenhouse uses hydroponics and LED lighting to simulate growing seasons, allowing hothouse plants like lemons and peppers to thrive. Is this a sign of how we will live in the future?

[story via the Guardian, Image from the Rea’s website]

Using nanotechnology for brighter lights and better solar power

Some examples of quantum dots, mere nanometres in sizeTwo good examples of nanotechnology in action today from Science Daily. The first comes in the field of solar technology. There are two main forms of solar nanotech: thin films of nanoparticles like titanium oxide doped with nitrogen, and so-called ‘quantum dots’, tiny semiconducting crystals that absorb the energy from light to release conducting electrons. Scientists from California, Mexico and China have shown that both methods can be combined into one material that performs better together than either method alone!

The second article discusses LED lights, which use far less energy than even energy-saving flourescent bulbs. However, whilst LEDs work great for smaller uses like book-lights, computers or mobile phones, they aren’t bright enough to light a room. The method to improve this is to make thousands of tiny holes on the bulb itself, allowing more light to escape the LED. Whilst before this process has been extremely time and money intensive, using nanotechnology lithography to imprint the holes makes the process far cheaper – which could lead to a massive growth in usage of LEDs in our homes and gadgets.

EDIT: As Larry mentions in the comments, there’s also been great progress making solar antennas using nanoscale spirals imprinted onto the material. This method could be printed on flexible materials and potentially is as much as 80% Efficient. Thanks for the heads up Larry!

[via Science Daily, image via NIST]