Tag: graphene

Powered by the Sun: The Artificial Leaf

solar_power1Despite progress made in recent decades, solar power still has some obstacles to overcome before it can be completely adopted. Thanks to several innovations, the price of manufacturing and installing solar panels has dropped substantially, intermittency remains a problem. So long as solar power remains limited by both geography and weather, we can expect to remain limited in terms of use.

And short of building Space-Based Solar Power (SBSP) arrays, or producing super-capacitor batteries with graphene – both of which are being explored – the only other option is to find ways to turn solar power into other forms of usable fuel. When the sun isn’t shining, people will need something else to power their homes, appliances, heating and AC. And given that the point is to reduce pollution, it will also have to be clean.

??????And that’s precisely what Daniel Nocera and his team are doing over at the University of Harvard. Their “artificial leaf” – a piece of silicon (solar cell) coated with two catalysts – is a means of turning sunshine into hydrogen fuel. Basically, when sunlight shines in, the leaf splits the water into bubbles of hydrogen and oxygen on each side, which can then be used in a fuel cell.

Efforts in the past to build similar solar cells have faltered, due largely to the costs involved. However, with the price of solar-related materials dropping in recent years, this latest device may prove commercially viable. And built to a larger scale, the device could provide a super-cheap and storable energy source from which could then be piped off and used in a fuel cell to make electricity. And combined with arrays of solar panels, we could have the energy crisis licked!

artificial-leafNocera and his team first announced the technology back in 2011, back when he was still a chemist at MIT. Since that time, they have published a follow-up paper showing how the team has improved the leaf’s efficiency, laying out future challenges, and how these might be overcome. Foremost amongst these are a field trial, with the eventual aim of building a commercial device for the developing world.

Beyond that, Nocera hopes to commercialize the technology through his company, the Massachusetts-based Sun Catalytix. Once realized, he plans to to put his dream of giving the poor “their first 100 watts of energy” into action. Here’s hoping he succeeds. The poor need power, and the environment needs a break from all our polluting!

Thank you all for reading the latest installment of PBTS! And be sure to check out this video of the artificial leaf in action:

The Future is Here: The (Super) Supercapacitor

supercapacitor_movieLast year, researchers at UCLA made a fantastic, albeit accidental, when a team of scientists led by chemist Richard Kaner devised an efficient method for producing high-quality sheets of graphene. This supermaterial, which won its developers the 2010 Nobel Prize in Physics, is a carbon material that is known for its incredible strength and flexibility, which is why it is already being considered for use in electronic devices, solar cells, transparent electrodes, and just about every other futuristic high-tech application.

Given the fact that the previous method of producing graphene sheets (peeling it with scotch tape) was not practical, the development of the new production process was already good news. However, something even more impressive happened when Maher El-Kady, a researcher in Kaner’s lab, wired a small square of their high quality carbon sheets to a lightbulb.

supercapacitor1After showing it to Dr. Kaner, the team quickly realized they had stumbled onto a supercapacitor material – a high-storage battery that also boasts a very fast recharge rate – that boasted a greater energy storage capacity than anything currently on the market. Naturally, their imaginations were fired, and their discovery has been spreading like wildfire through the engineering and scientific community.

The immediate benefit of batteries that use this new material are obvious. Imagine if you will having a PDA, tablet, or other mobile device that can be charged within a matter of seconds instead of hours. With batteries so quick to charge and able to store an abundant supply of volts, watts, or amperes, the entire market of consumer electronics would be revolutionized.

electric_carBut looking ahead, even greater applications become clear. Imagine electric cars that only need a few minute to recharge, thus making the gasoline engine all but obsolete. And graphene-based batteries could be making an impact when it comes to the even greater issue of energy storage with regards to solar and other renewable energy sources.

In the year since they made their discovery, the researchers report that El-Kady’s original fabrication process can be made even more efficient. The original process involved placing a solution of graphite oxide on a plastic surface and then subjecting it to lasers to oxigenate and turn the solution into graphene. A year ago, the team could produce only a few sheets at a time, but now have a scalable method which could very quickly lead to manufacturing and wide-scale technological implementation.

solar_array1As it stands, an electric car with a recharge rate of a few minutes is still several years away. But Dr. Kaner and his team expect that graphene supercapacitors batteries will be finding their way into the consumer world much sooner than anyone originally expected.  According to Kaner, his lab is already courting partners in industry, so keep your eyes pealed!

Combined with the new technologies of lithium-ion and nanofabricated batteries, we could be looking at a possible solution to the worlds energy problem right here. What’s more, it could be the solution that makes solar, wind, and other renewable sources of energy feasible, efficient, and profitable enough that they will finally supplant fossil fuels and coal as the main source of energy production worldwide.

Only time will tell… And be sure to check out the video of Dr. Kaner and El-Kady showing off the process that led to this discovery:


Source: IO9.com