Posted on 12/11/2014 3:24:14 PM PST by 2ndDivisionVet
In research out of the University of Manchester in the UK led by Nobel Laureate Andre Geim, it has been shown that the one-atom-thick materials graphene and hexagonal boron nitride (hBN), once thought to be impermeable, allow protons to pass through them. The result, the Manchester researchers believe, will be more efficient fuel cells and the simplification of the heretofore difficult process of separating hydrogen gas for use as fuel in fuel cells.
This latest development alters the understanding of one of the key properties of graphene: that it is impermeable to all gases and liquids. Even an atom as small as hydrogen would need billions of years for it to pass through the dense electronic cloud of graphene. In fact, it is this impermeability that has made it attractive for use in gas separation membranes.
But as Geim and his colleagues discovered, in research that was published in the journal Nature, monolayers of graphene and boron nitride are highly permeable to thermal protons under ambient conditions. So hydrogen atoms stripped of their electrons could pass right through the one-atom-thick materials.
The surprising discovery that protons could breach these materials means that that they could be used in proton-conducting membranes (also known as proton exchange membranes), which are central to the functioning of fuel cells. Fuel cells operate through chemical reactions involving hydrogen fuel and oxygen, with the result being electrical energy. The membranes used in the fuel cells are impermeable to oxygen and hydrogen but allow for the passage of protons.
It is these proton exchange membrane fuel cells that are thought to be the most viable fuel cell design for replacing the internal combustion engine in vehicles. However, the polymer-based membranes that have been used to date suffer from fuel crossover that limits their efficiency and durability.
The implication of this latest research is that graphene and hBN could be used to create a thinner membrane that would be more efficient while reducing fuel crossover and cell poisoning. The end result is that it could give the fuel cell the technological push that it has needed to make hydrogen a viable alternative to fossil fuels.
Another, even more remarkable prospect highlighted by this discovery is that these one-atom-thick materials could be used to extract hydrogen from a humid atmosphere. This could be a huge bend in the road that points us towards the so-called hydrogen economy.
One of the inconvenient truths about fuel cells for powering automobiles is that it is extremely costly and energy intensive to isolate hydrogen gas. The main push in nanomaterials for hydrogen gas separation has been artificial photosynthesis in which sunlight rather than electricity is used to split the hydrogen from a water molecule. In fact, another two-dimensional material, molybdenum sulfide (MoS2), has been used as a somewhat effective catalyst for producing hydrogen gas in a solar water-splitting process.
But what Geim and his colleagues are suggesting with this latest research stands this paradigm on its head. It is conceivable, based on this research, that hydrogen production could be combined with the fuel cell itself to make what would amount to a mobile electric generator fueled simply by hydrogen present in air.
“When you know how it should work, it is a very simple setup,” said Marcelo Lozada-Hidalgo, a PhD student and corresponding author of this paper, in a press release. “You put a hydrogen-containing gas on one side, apply a small electric current, and collect pure hydrogen on the other side. This hydrogen can then be burned in a fuel cell.”
Lozada-Hidalgo added: “We worked with small membranes, and the achieved flow of hydrogen is of course tiny so far. But this is the initial stage of discovery, and the paper is to make experts aware of the existing prospects. To build up and test hydrogen harvesters will require much further effort."
While some have been frustrated that Geim has focused his attention on fundamental research rather than becoming more active in the commercialization of graphene, he may have just cracked open graphene’s greatest application possibility to date.
“As a percentage, maybe, but in absolute millions of tons, it’s quite a bit.”
So wouldn’t you then have to put millions of tons of air through your filter to extract that “quite a bit”?
My point is that, even though we’re in a closed system and won’t be “creating” new water vapor you look over LA with the traffic it will be almost a constant fog and we’ll really hear how the hydrogen fuel cell was another bad idea.
Cypress Hill.
It is to good to be true.
Every single one of these schemes works, for a while. Then the membrane gets poisoned and the cell stops working. You can burn out the poison but it takes more energy than it is worth to do it.
That is the real problem, not the straw-man setup here in the article.
If you can figure out how to build a system around it many solids can work here as a membrane but they only start running at 600C.
The Research and Development Degree of Difficulty, or RD3 is a “V” or 5 which combined with a Technology Readiness Level, or TRL of 2 means no.
BTW the math says this only has a 0.032% chance of working.
This is hugh and series. Unfortunately it’s not going anywhere as the EPA will put a stop to it.
/johnny
In all seriousness, the applications for graphene are numerous. Specifically in semi-conductor industry.
We already do. Burning gasoline produces water.
It is my understanding that the water need not be released as a vapor.
Indeed, it is already pure so why waste purified water?
Cars will just have to pee.
“It’s easy to move air.”
Yea, but it takes energy to move it...
There is no evidence that a greenhouse effect even exists and, as I gave numerous references to, a lot of evidence that it doesn’t exist.
Sorry for double post still adapting to new iPad.
The greenhouse effect is the idea that our atmosphere retains the heat that keeps the planet warm. It doesn't. Heat in the atmosphere easily escapes into space. A greenhouse is a closed system which isolates air inside the greenhouse from air outside the greenhouse. Our atmosphere is the opposite. All of our atmosphere is entirely open to space which is an entirely different medium.
What really heats our planet could more accurately be described as a Swimming Pool Effect. The sun heats the pool (the oceans) and the pool radiates heat to the atmosphere where it remains very temporarily.
There is also a weak Roman Bath House Effect that contributes to heating both the pool and the atmosphere. The molten core of the earth contributes heat to the oceans and land masses, which in turn heat the atmosphere, like the wood-fired heating system in a Roman bath house which heats the pool and surrounding stone of the floor from beneath.
FWIW I’m not politicizing the science and neither were the sources I provided.
Global warming issue. The owners will be taxed into the next century.
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