New material steals oxygen from the air

September 30, 2014
Professor Christine McKenzie in the lab at University of Southern Denmark with her colleagues. Credit: University of Southern Denmark

Researchers from the University of Southern Denmark have synthesized crystalline materials that can bind and store oxygen in high concentrations. Just one spoon of the substance is enough to absorb all the oxygen in a room. The stored oxygen can be released again when and where it is needed.

We do fine with the 21 per cent oxygen in the air around us. But sometimes we need oxygen in higher concentrations; for example lung patients must carry heavy oxygen tanks, cars using fuel cells need a regulated . Perhaps one day in the future even sunlight-driven "reversible" fuel cells will be made. With these we will have to separate oxygen from hydrogen in order to recombine them in order to get energy.

Now Professor Christine McKenzie and postdoc Jonas Sundberg, Department of Physics, Chemistry and Pharmacy at the University of Southern Denmark have synthesized a material that absorb oxygen in large quantities and store it.

"In the lab, we saw how this material took up oxygen from the air around us", says Christine McKenzie.

The new material is crystalline, and using x-ray diffraction the researchers have studied the arrangement of atoms inside the material when it was filled with oxygen, and when it was emptied of oxygen.

Oxygen comes and goes in many places

The fact that a substance can react with oxygen is not surprising. Lots of substances do this - and the result is not always desirable: Food can go rancid when exposed to oxygen. On the other hand a wine's taste and aroma is changed subtly when we aerate it - but not with too much oxygen! Our bodies cannot function if we do not breathe.

New material steals oxygen from the air
The crystalline material changes color when absorbing or releasing oxygen. Crystals are black when they are saturated with oxygen and pink when the oxygen has been released again. Credit: University of Southern Denmark

"An important aspect of this new material is that it does not react irreversibly with oxygen - even though it absorbs oxygen in a so-called selective chemisorptive process. The material is both a sensor, and a container for oxygen - we can use it to bind, store and transport oxygen - like a solid artificial hemoglobin", says Christine McKenzie.

The material is so effective at binding oxygen, that only a spoon of it is enough to suck up all the oxygen in a room. The researchers' work indicates that the substance can absorb and bind oxygen in a concentration 160 times larger than the concentration in the air around us.

"It is also interesting that the material can absorb and release oxygen many times without losing the ability. It is like dipping a sponge in water, squeezing the water out of it and repeating the process over and over again", Christine McKenzie explains.

Once the oxygen has been absorbed you can keep it stored in the material until you want to release it. The oxygen can be released by gently heating the material or subjecting it to low oxygen pressures.

Heat and pressure releases the stored oxygen

"We see release of oxygen when we heat up the material, and we have also seen it when we apply vacuum. We are now wondering if light can also be used as a trigger for the material to release oxygen – this has prospects in the growing field of artificial photosynthesis", says Christine McKenzie.

The key component of the new material is the element cobalt, which is bound in a specially designed organic molecule.

"Cobalt gives the new material precisely the molecular and electronic structure that enables it to absorb oxygen from its surroundings. This mechanism is well known from all breathing creatures on earth: Humans and many other species use iron, while other animals, like crabs and spiders, use copper. Small amounts of metals are essential for the absorption of oxygen, so actually it is not entirely surprising to see this effect in our new material", explains Christine McKenzie.

Depending on the atmospheric oxygen content, temperature, pressure, etc. it takes seconds, minutes, hours or days for the substance to absorb oxygen from its surroundings. Different versions of the substance can bind oxygen at different speeds. With this complexity it becomes possible to produce devices that release and/or absorb oxygen under different circumstances – for example a mask containing layers of these in the correct sequence might actively supply a person with oxygen directly from the air without the help of pumps or high pressure equipment.

"When the substance is saturated with oxygen, it can be compared to an containing pure oxygen under pressure - the difference is that this material can hold three times as much oxygen," says Christine McKenzie.

"This could be valuable for lung patients who today must carry heavy oxygen tanks with them. But also divers may one day be able to leave the oxygen tanks at home and instead get oxygen from this material as it "filters" and concentrates oxygen from surrounding air or water. A few grains contain enough oxygen for one breath, and as the material can absorb from the water around the diver and supply the diver with it, the diver will not need to bring more than these few grains".

Explore further: Research pinpoints role of 'helper' atoms in oxygen release

More information: Oxygen chemisorption / desorption in a reversible single-crystal-to-single-crystal transformation. Jonas Sundberg, Lisa J. Cameron, Peter D. Southon, Cameron J. Kepert and Christine J. McKenzie.

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antialias_physorg
5 / 5 (5) Sep 30, 2014
for example a mask containing layers of these materials in the correct sequence might actively supply a person with oxygen directly from the air without the help of pumps or high pressure equipment.

Space suits less the bulky oxygen tanks? Coupled with the article on space suits made of thin fabrics one youd imagine a material like this interwoven in the fabric to release oxygen on demand. That would be a really radical departure from current designs.
Goika
Sep 30, 2014
This comment has been removed by a moderator.
axemaster
5 / 5 (5) Sep 30, 2014
Yeah I'm having a hard time buying this myself - it sounds to have a far greater density than pure liquid oxygen!
trux
4.4 / 5 (7) Sep 30, 2014
They tell a spoonful of the material can absorb all the oxygen in a room, but they do not tell how big room, and how big spoon. But because they also write that it can bind oxygen in a concentration 160 times larger than the concentration in the air around us, it is clear that the room cannot be bigger than 5x160 spoons (5 times because of the approx. 1/5 content of O2 in the air). So the claim about the spoon sucking O2 from entire room is right but only for rooms not much bigger than a cigarette box, or for very giant spoons. It is of course nonsense that a few grams of the material could suck tens of kg of O2. It would be nice if physorg authors checked their facts prior publishing, or if they could let the scientist authorize the articles. Such sensational articles do not do any good neither for Phys.org, neither for the science.
trux
5 / 5 (3) Sep 30, 2014
PS: just thinking about it again, I believe that what they mean is that the spoonful of the material can absorb and release all O2 from a room, but not in once, but rather continuously in cycles over longer time. It is a pity they did not write it clearly enough.

This could be even more interesting it the material was able to absorb also O2 dissolved in water - it could be used also for an underwater breathing apparatus, sort of artificial gills.
antialias_physorg
4.2 / 5 (5) Oct 01, 2014
You can read the full article here:
https://findresea...636j.pdf

At a quick glance I couldn't find any volumetric info (comparison of substance volume vs. bound O2)..but I only skimmed it.
Returners
2.7 / 5 (7) Oct 01, 2014
The density of the crystal the size of a teaspoon after absorbing the oxygen from an entire 12ft by 12ft by 8ft room(bedroom) would be 6.5 kilograms per teaspoonful.

That's clearly an exaggeration, because that's more dense than core of the Sun.

Was this "spot the fake article" day?
Eseta
Oct 01, 2014
This comment has been removed by a moderator.
trux
5 / 5 (4) Oct 01, 2014
[This is also hard to believe. The volume density of oxygen in air is much lower than this one of any solid material...

I am afraid I do not understand what exactly you wanted to tell, but if a teaspoon of the material (say 5ml) can absorb 160 times its volume of O2 at atmospheric pressure, it gives 800ml of oxygen, which then corresponds roughly to 4 liters of air (or about smaller vital lung volume). Could be 2l if the spoon was 2.5ml, or perhaps 15 liters or more at a soup spoon.

However, this is all rather irrelevant, because, as I concluded earlier, the article when it speaks about a teaspoon of material sucking O2 from entire room, clearly (though very misleadingly) does not mean that it absorbs the gas in once, but that it could extract the oxygen from a room-size volume if it worked continuously over longer period (say 800 ml at a time, so in couple of thousands of cycles)
trux
5 / 5 (5) Oct 01, 2014
OK, so I looked at the document, and the 160-fold absorption rate is indeed correct, but it applies to the air equivalent. If applied to O2 at atmospheric pressure, the factor is just 32. Still, it is much higher than the binding capacity of hemoglobin (1.34 ml of atm. O2 per 1 mg of Hb).

To adjust the previous calculation, a 5ml spoon of the material could absorb 160 ml of O2 at 1 bar (air volume of 800 ml - around a slightly bigger breath of an adult). For a room of 50 m3, you would need over 60,000 of absorption/release cycles.
trux
4 / 5 (4) Oct 01, 2014
The volume density of oxygen in air is much lower than this one of any solid material...

I am still not sure to understand your comment correctly, but have the feeling you mistook the chemical binding of O2 by the material (just like at hemoglobin) to oxygen dissolved in the material. In case of a dissolved O2, your comment would make sense, because it would be indeed difficult for the material to absorb O2 at a partial pressure above the ambient level, but it is not necessarily the case at the chemically based absorption. Assuming I understood you well, I think your commend about the distorted logic of scientist may have been premature and undeserved.
Captain Stumpy
3.7 / 5 (3) Oct 01, 2014
You can read the full article here:
https://findresea...636j.pdf

At a quick glance I couldn't find any volumetric info (comparison of substance volume vs. bound O2)..but I only skimmed it
@antialias_physorg
Thanks for that link!
Appreciate it!
Captain Stumpy
2.3 / 5 (3) Oct 01, 2014
Apparently the ability to calculate doesn't still imply the ability to think logically (as it's quite common for contemporary physicists, who are well trained in math - but not in logical thinking)
@zephir
personal conjecture not based upon evidence
Perhaps this is your problem, but keep your transference posts to yourself
Your argument has to do with your continued support of a failed, debunked pseudoscience in which you refuse to admit the empirical evidence exists debunking it... therefore anyone who reads your posts can rightfully assume (logically) that you are the one who is not thinking logically (nor sanely)

Physicists debunked your religious belief which was downgraded from a theory to a philosophy - Logic, empirical evidence and math

They ignore your pleading to accept other failed crackpot ideas and pseudoscience & continually refute you with reality - Logic

your acceptance and tenacious clinging to a failed pseudoscience?
NOT logic!
http://sci-ence.o...-flags2/
antialias_physorg
5 / 5 (3) Oct 01, 2014
Since we're just guessing I went the direct route and shot professot McKenzie an email to this effect:

Dear Professor McKenzie,

There has been an article circulating various popular/laymen science reporting sites (phys.org, physnews.com, et. al) about your article in which the claim is made that the organic molecule containing cobalt:
"Just one spoon of the substance is enough to absorb all the oxygen in a room"

Some of us have been having a discussion on this in one of the comment sections as the claim seems implausible (as that would quickly exceed the density of liquid oxygen - even given a very tiny room). Not being full experts on the subject I'd you could give us a quick yes/no answer as this claim?

Best Regards
....


He kindly answered (including a number of papers (if anyone is interested PM me):
[cont]
antialias_physorg
5 / 5 (7) Oct 01, 2014
[cont]

Reply email:
Dear ...

This is of course completely wrong!

Please see a couple of articles attached (where I believe there are no mistakes!). But the O2 concentration is greater than in oxyhemoglobin.

I think it can store about 3 x the amount of a pressurized gas cylinder. (so about 160 x concentration of atm press air or 32 x pure O2 gas at atm. press.)

Best regards

Christine McKenzie


When in doubt - go to the source :)
Captain Stumpy
5 / 5 (1) Oct 01, 2014
He kindly answered (including a number of papers (if anyone is interested PM me):
@AA_P
Interested
can't PM you on PO
do you have a sciforums or saposjoint page log-in?
Cosmoquest?
You can find me at all three under TruckCaptainStumpy
Captain Stumpy
5 / 5 (1) Oct 01, 2014
@antialias_physorg
I would recommend setting yourself up at saposjoint
go here: http://saposjoint.net/Forum/

heavily moderated
no RC to bother anyone
easy to use

Tell the MOD or ADMIN Sapo that you want to forward some pages from PO and your message from Professor McKenzie, He is understanding

antialias_physorg
3 / 5 (2) Oct 01, 2014
Interested

I just created a temporary mail account (24h)
someguyATalivance.com
just shoot me an email there and I'll send them to you (total about 2MB)

trux
5 / 5 (1) Oct 01, 2014
I think it can store about 3 x the amount of a pressurized gas cylinder. (so about 160 x concentration of atm press air or 32 x pure O2 gas at atm. press.)

@antialias_physorg it was not really necessary to bother the professor with it, it is exactly what I told above, and what is written in the document you kindly linked earlier.

But when you are already in contact with the author, couldn't you ask Professor McKenzie whether the substance would work in water too (extracting O2 dissolved in water)? That would be immensely interesting too.
antialias_physorg
3.7 / 5 (3) Oct 01, 2014
But when you are already in contact with the author, couldn't you ask Professor McKenzie whether the substance would work in water too (extracting O2 dissolved in water)? That would be immensely interesting too.

Well, I don't really want to bug her too much, as she's undoubtedly very busy (it's always very nice when someone takes time out of their workday to answer these kinds of things, but we shouldn't push it). But send me an email to the above address and I'll forward the articles she sent to you. Maybe there's something relevant in there that I haven't seen yet.

antialias_physorg
3 / 5 (2) Oct 01, 2014
But when you are already in contact with the author, couldn't you ask Professor McKenzie whether the substance would work in water too (extracting O2 dissolved in water)?

Found something: From what I get from one of the papers she sent there's a certain partial oxygen pressure needed for the absorption to take place. (Absorption was done by bubbling an Argon/Oxygen mix through the dissolved substance).
I don't think you'll find that kind of oxygen pressure in water naturally.
trux
5 / 5 (2) Oct 01, 2014
I don't think you'll find that kind of oxygen pressure in water naturally.

Well, it depends how big ppO2 they used (how much Argon was in the mixture), but the ppO2 at the surface of the ocean is close to the atmospheric ppO2. It then raises with the depth (thanks to the ambient hydrostatic pressure), and only decreases at greater depths, where the saturation starts to decrease faster than the increase of the hydrostatic pressure. So I would not exclude it could work, but I will read through the documents you kindly forwarded. Thanks!
MaxC500
not rated yet Oct 05, 2014
I am probably mistaken but i thought the volume of dry air contains 78% nitrogen, 21% oxygen. So only about 1/5 is oxygen. Meaning that small room of some (3 meters by 4 meters by 2.5 meters high) 30 cubic meters times divided by 5 contains some 6 cubic meters of oxygen or 6000 cubic decimeters. If this is divided by the absorption rate of 160 you would need 37.5 cubic decimeters of this stuff to suck the air from a small room, much more than a thee spoon but still very interesting (and i might well be mistaken). If what i say is correct and 1 regular oxygen tanks contain some 30 cubic decimeter than 1 oxygen tank could contain almost enough of the powder for the oxygen of an entire room. But the volume would also expand so i`m not at all sure what to expect of this material and its possible applications.
antialias_physorg
5 / 5 (1) Oct 05, 2014
so i`m not at all sure what to expect of this material and its possible applications.

Read the other comments. Your questions shall be answered.
trux
not rated yet Oct 05, 2014
As antialias_physorg wrote, your concerns are addressed above in other comments. In brief, the interest of the material is not replacing oxygen tanks because of its bigger storing capacity, but thank to its capability to produce oxygen on-the-go. The storing capacity of the material is much lower than commonly used gas tanks (equivalent of 32 bars of pure O2, or 160 bars of compressed air at the material, vs. 200-300 bars at pressurized tanks). On the other hand, the binding capacity is significantly higher than at hemoglobin (approximately 30 times higher). Only a spoonful of the material could be sufficient to construct a small respiratory device able to supply oxygen for a single person - much better portable and with possibly unlimited run-time in comparison with current portable O2 supplies.

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