Scientists have built the world’s thinnest electric generator – and it’s only one atom wide


Researchers have created a graphene-like material that generates electricity every time its stretched, and could power the wearable technology of the future.

Scientists from the Georgia Institute of Technology and Columbia Engineering in the US have shown they can generate electricity from a layer of material that’s just one atom thick. The generator is made from molybdenum disulphide (MoS2), which is a clear, flexible and extremely light material that opens up huge possibilities for the future of electricity generation.

The new electrical generator is an example of piezoelectricity, or electricity that’s generated from pressure. Piezoelectric materials have huge potential to be used to create materials that can charge devices, such as footwear that powers an iPod. But until now, scientists have struggled to make these materials thin and flexible enough to be practical.

However, it’s been predicted that a substance capable of forming single-atom-thick molecules, or two-dimensional layers, would be highly piezoelectric.

Now the scientists have proved that this is the case for the first time ever. Their results have beenpublished in Nature.

To test whether MoS2 would be piezoelectric on the atomic scale, the team flaked off extremely thin layers of MoS2 onto a flexible substrate with electrical contact.

Because of the way these flakes were created, each had a slightly different number of layers – for example, while some were just one-atom-thick, others were eight-atoms-thick.

The scientists tested the piezoelectric response of these flakes by stretching the material, and measuring the flow of electrons into an external circuit.

Interestingly, they discovered that when the material had an odd number of layers, it generated electricity when stretched. But when it had an even number of layers, there was no current generated.

A single one-atom-thick layer of the material was able to generate 15 megavolts of electricity when stretched.

They also found that as the number of layers increased, the amount of current generated decreased, until eventually the material got too thick and stopped producing any electricity at all.

Computational studies suggest that this is because the atomic layers all have random orientations, and they eventually cancel each other out.

The research team also arranged these one-atom-thick layers of MoS2 into arrays, and found that together they were capable of generating a large amount of electricity.

This suggests that they’re a promising candidate for powering nano electronics, and could be used to create wearable technologies.

“This material – just a single layer of atoms – could be made as a wearable device, perhaps integrated into clothing, to convert energy from your body movement to electricity and power wearable sensors or medical devices, or perhaps supply enough energy to charge your cell phone in your pocket,” said James Hone, professor of mechanical engineering at Columbia engineering and co-leader of the research,

Wind Power Blades Get Bigger, Turbines Get Smarter.


A look at tomorrow’s turbines

Wind Power Future
Metal inserts built into the carbon-fiber blade during manufacture mean the root end, bolted to the hub, can be slimmer, stronger, and more aerodynamically efficient. • Fabricating the carbon fiber in modular pieces, rather than one long blade, ensures the material’s consistency and reduces the risk of failure. • An erosion-protection material molded into the leading edge of the blade reduces wear and tear over the blade’s lifetime.
Graham Murdoch

In 2012, wind power added more new electricity production in the U.S. than any other single source. But even with 60 gigawatts powering 15 million homes, wind supplants just 1.8 percent of the nation’s carbon emissions. Tomorrow’s turbines will have to be more efficient, more affordable, and
in more places.

The Supersize Route

Bigger Blades

Big rotors generate more electricity, particularly from low winds, but oversize trucks hauling blades the length of an Olympic pool can’t reach many wind-energy sites. Blade Dynamics fabricates its 160-foot, carbon-fiber blade in multiple pieces, which can then be transported by standard trucks and assembled at a nearby location. It’s a stepping-stone for 295-foot and 328-foot blades now being designed for offshore turbines. (Currently, the world’s longest prototype is 274 feet.) The colossal size should enable 10- to 12-megawatt turbines, double the generation capacity of today’s biggest models.

Wind Power Scale
Graham Murdoch

The Networked Solution

Smarter Turbines

Reducing the variability of wind energy could position it to compete as a stable source of power. General Electric’s new 2.5-megawatt, 394-foot-diameter wind turbine has an optional integrated battery for short-term energy storage. It also connects to GE’s so-called Industrial Internet so it can share data with other turbines, wind farms, technicians, and operations managers. Algorithms analyze 150,000 data points per second to provide precise region-wide wind forecasts and enable turbines to react to changing conditions, even tilting blades to maximize power and minimize damage as a gust hits.

The Hybrid Hail Mary

Man-Made Thunderstorm Power

Solar Wind Energy’s downdraft tower is either ingenious or ludicrous. The proposed 2,250-foot-high concrete tower will suck hot desert air into its hollow core and infuse it with moisture, creating a pressure differential that spawns a howling downdraft. “You’re capturing the last 2,000 feet of a thunderstorm,” says CEO Ron Pickett. The man-made tempest would spin wind turbines that could generate up to 1.25 gigawatts (though it’s designed to operate at 60 percent capacity) on the driest, hottest summer days—more than some nuclear power plants. The Maryland-based company plans to break ground in Arizona as soon as 2015, provided it can secure $900 million in funding—a large sum but perhaps not outlandish when compared with a $14-billion nuclear reactor now under construction.