Sciencemadness Discussion Board

Singlet Oxygen Luminescence in a Home Lab

AJKOER - 17-7-2014 at 11:48

First, some background on Singlet oxygen (link: http://www.researchgate.net/publication/15390248_Singlet_mol... to quote from the abstract:

"A study of the pH profile of the decomposition of aqueous hypochlorite has revealed the evolution (onset at pH 8) of single (1 delta g) molecular oxygen (singlet spin state dioxygen) detected spectroscopically (1268 nm), prior to the appearance of chlorine (onset at pH 5.5). The possible mechanism of the singlet state dioxygen evolution is presented, and the origin of its chloride ion dependence is discussed, especially in reference to chloride ion dependence of singlet molecular oxygen evolution in biological systems. Recent epidemiological analyses of the correlation of human cancer with chlorinated water supplies focus attention on the singlet oxygen mechanisms of DNA lesion formation."

Here is a text quote relating to preparation:

"The generation of singlet molecular oxygen by the chemiluminescent reaction of hydrogen peroxide with aqueous hypochlorite is well known and is now a standard method (5-9)"

The full article is available at https://www.google.com/url?sa=t&source=web&rct=j&... and see also sample preparation at http://www1.chem.leeds.ac.uk/delights/texts/expt_27.html

Here is the experiment I performed which resulted in limited amount of luminescence from Singlet oxygen. I added, 2 ice cubes, 80 cc of bleach (8.25% NaClO), 30 grams of NaCl and 30 grams of CaCl2 which has been previously exposed to moisture (forming CaCl2.CaO) to a wide mouth vessel which is sealed with a funnel. The funnel has also 2 pieces of ice, some 3% H2O2 and is fitted with a plug (non-organic) to create a slow drip of hydrogen peroxide.

What I observed in complete darkness (allow your eyes to adjust before starting the H2O2 drip) was some luminescence that was intensified with shaking, passing hot water over the vessel and also by adding another 30 grams of CaCl2.CaO.

What I have in effect created was a highly ionic cold hypochlorite solution (as opposed to passing Cl2 gas into conc aqueous NaOH) that is slowly reacted with dilute H2O2 (as opposed to the standard preparation with 30% H2O2) creating some Singlet oxygen. Some chemistry per this reference https://www.google.com/url?sa=t&source=web&rct=j&... to quote:

"Decomposition of hydrogen peroxide with bleach

H2O2 + OCl- ----) HO2- + H OCl ---) HO- + HOOCl ---) H2O + ClOO-
ClOO- ---) Cl- + 1O2"

I invite others to experiment and suggest modifications to improve the luminescence phenomena.

The production of Singlet oxygen is the first step also in working with the chemically active gas which has a life span of at most 75 minutes. Note also, water is an effective quenching agent (destroying the gas forming H2O2).

[Edited on 17-7-2014 by AJKOER]

aga - 17-7-2014 at 12:10

C O O L !

nice one AJ

any photos ?

AJKOER - 17-7-2014 at 12:21

The problem is my preparation so far requires patience with just short periods of more intense luminescence. It is important that one keeps one eyes adjusted to the dark.

Taking pictures of such a phenomena in the dark has proved challenging (at least to me).

aga - 17-7-2014 at 13:33

As is my wont, i shall give your experiment a go.

Hopefully with photographs.

Thank you for posting details of the experiment so that it can actually be repeated.

AJKOER - 17-7-2014 at 14:48

Quote: Originally posted by AJKOER  
.........

What I have in effect created was a highly ionic cold hypochlorite solution (as opposed to passing Cl2 gas into conc aqueous NaOH) that is slowly reacted with dilute H2O2 (as opposed to the standard preparation with 30% H2O2) creating some Singlet oxygen. Some chemistry per this reference https://www.google.com/url?sa=t&source=web&rct=j&... to quote:

"Decomposition of hydrogen peroxide with bleach

H2O2 + OCl- ----) HO2- + H OCl ---) HO- + HOOCl ---) H2O + ClOO-
ClOO- ---) Cl- + 1O2"
..........


I also have a theoretical speculation that someone may wish to explore. Rewriting the equation above for 2 HOCl, we have:

2 H2O2 + 2 HOCl ----) 2 H2O + 2 HOOCl ---) 2 H2O + 2 H+ + 2 ClOO-

ClOO- ---) Cl- + 1O2"

For a highly ionic concentrated solution of Hypochlorous acid, the equilibrium of the reaction:

2 HOCl = H2O + Cl2O

moves to the right, so substituting Cl2O for 2 HOCl in the reaction chain above, which also proceeds in concentrated ionic conditions, implies:

2 H2O2 + Cl2O ----) H2O + 2 HOOCl ---) H2O + 2 H+ + 2 ClOO-
ClOO- ---) Cl- + 1O2

So my speculation is that dichlorine monoxide may be precursor to Singlet oxygen as well. Consequently, preparations path for Cl2O may be tested with H2O2 as a possible path to Singlet oxygen.
------------------------------------------------

Came across a new path to Singlet oxygen, see http://pubs.rsc.org/en/Content/ArticleLanding/2012/CP/C2CP41... . To quote from the abstract:

"Non-basic hydrogen peroxide was found to be very easy to react with Cl2 to produce singlet oxygen O2(a1Δg) (i.e. the molecular oxygen in its first electronic excited state) when an H+ absorbent such as C5H5N, CH3COONH4, HCOONH4 or NH4F was added into H2O2 aqueous solution, and the long concealed fact that molecular H2O2 can react with Cl2 to produce O2(a1Δg) was then uncovered. It is only when an H+ absorbent has provided a stronger base than H2O to absorb the H+ produced during the reaction that O2(a1Δg) can be produced."

[Edited on 18-7-2014 by AJKOER]

woelen - 17-7-2014 at 22:40

Making visible amounts of singlet oxygen is easy and gives quite a powerful red glow. Just take swimming pool chlorine (the shock-treatment sodium dichlorocyanurate works best, but others also work) and add 20...30% H2O2:

http://woelen.homescience.net/science/chem/exps/chemlum/inde...

CHRIS25 - 18-7-2014 at 00:04

Quote: Originally posted by AJKOER  
The problem is my preparation so far requires patience with just short periods of more intense luminescence. It is important that one keeps one eyes adjusted to the dark.

Taking pictures of such a phenomena in the dark has proved challenging (at least to me).

No idea what camera you have or your knowledge so I will give details: Taking images in the dark is easy once I show you how:
1. Set the aperture to its widest - 1.4, 1.8 if you can't get this low and 4.0 is your lowest then do this.
2.Set ISO rating to highest: 800 1600 or 2400. (noise will not be that bad)
3. Set the focal point to the liquid using manual (not automatic focus ) and set the focal distribution dots to a single point, not average or centre weighted, but pin point) and make sure that the focus is not on the glass but inside the glass this is why you ned to adjust focus by hand
4. you will need to have a shutter speed to about 4 or 8 seconds.
To do all the above you need to set camera on tripod or stacks of books, and importantly use a timer on the camera, hand held shot will destroy the image - no sharpness at such low shutter speeds.
Do Not use flash, it kills photographs, and throw away all automation, you want complete control.
Any questions ask away. I too would like to see these images.

AJKOER - 18-7-2014 at 04:23

Thanks you Woelen for the link and the intensely cool pictures!

The swimming pool salt of which Woelen speaks may have finally and unfortunately attracted attention.

In the north east of these United States, both Home Depot and Lowes near me have decided (at the same time no less, curious) to remove all chemicals associated with swimming pools (that department no longer exist!).

The TCCA and its sodium salt recomended by Woelen produce HOCl with water. The sodium salt probably works best due to pH effects per sources I cited previously.
-------------------------------------------------------

Here are some interesting reactions between Singlet oxygen and Nitrous oxide (N2O). To quote (link: http://www.ccpo.odu.edu/~lizsmith/SEES/ozone/class/Chap_5/5_... ):

"Reactive nitrogen species are formed from N2O via the reaction of nitrogen dioxide with the singlet D oxygen atom to form two molecules of nitric acid.

N2O + O(1D) --> 2 NO

This reaction transfers nitrogen from the inert species, N2O, into the reactive species, NO.

Another way that N2O is lost is via photolysis. An energetic UV photon is able to dissociate N2O into molecular nitrogen, N2, and the singlet D oxygen atom.

N2O+hc/lambda --> N2+O(1D) "

So, it is claimed that active singlet oxygen may react with the usually inert N2O to form Nitric oxide, a precursor to NO2 and HNO3. Also, applying a low pressure Hg lamp (or possibly a flourescent lamp) to N2O, may form singlet oxygen as well, cool.

I have ordered some N2O for some more experiments.

[Edited on 18-7-2014 by AJKOER]

blogfast25 - 18-7-2014 at 08:10

Quote: Originally posted by CHRIS25  

Taking pictures of such a phenomena in the dark has proved challenging (at least to me).[/rquote]
No idea what camera you have or your knowledge so I will give details: Taking images in the dark is easy once I show you how:
1. Set the aperture to its widest - 1.4, 1.8 if you can't get this low and 4.0 is your lowest then do this.
2.Set ISO rating to highest: 800 1600 or 2400. (noise will not be that bad)
3. Set the focal point to the liquid using manual (not automatic focus ) and set the focal distribution dots to a single point, not average or centre weighted, but pin point) and make sure that the focus is not on the glass but inside the glass this is why you ned to adjust focus by hand
4. you will need to have a shutter speed to about 4 or 8 seconds.
To do all the above you need to set camera on tripod or stacks of books, and importantly use a timer on the camera, hand held shot will destroy the image - no sharpness at such low shutter speeds.
Do Not use flash, it kills photographs, and throw away all automation, you want complete control.
Any questions ask away. I too would like to see these images.


Very interesting.

I've had much trouble recently photographing the emission spectra of hydrogen and helium (and others), using a digital Canon 350. I'm not much of a photographer.

Ironically I obtained better results with a digital Canon of much lower spec (almost 'instamatic')!

CHRIS25 - 18-7-2014 at 10:07

Quote: Originally posted by blogfast25  
Quote: Originally posted by CHRIS25  

Taking pictures of such a phenomena in the dark has proved challenging (at least to me).[/rquote]
No idea what camera you have or your knowledge so I will give details: Taking images in the dark is easy once I show you how:
1. Set the aperture to its widest - 1.4, 1.8 if you can't get this low and 4.0 is your lowest then do this.
2.Set ISO rating to highest: 800 1600 or 2400. (noise will not be that bad)
3. Set the focal point to the liquid using manual (not automatic focus ) and set the focal distribution dots to a single point, not average or centre weighted, but pin point) and make sure that the focus is not on the glass but inside the glass this is why you ned to adjust focus by hand
4. you will need to have a shutter speed to about 4 or 8 seconds.
To do all the above you need to set camera on tripod or stacks of books, and importantly use a timer on the camera, hand held shot will destroy the image - no sharpness at such low shutter speeds.
Do Not use flash, it kills photographs, and throw away all automation, you want complete control.
Any questions ask away. I too would like to see these images.


Very interesting.

I've had much trouble recently photographing the emission spectra of hydrogen and helium (and others), using a digital Canon 350. I'm not much of a photographer.

Ironically I obtained better results with a digital Canon of much lower spec (almost 'instamatic')!

This is possible for two reasons:
1. The distance between the lens and RGB sensor is much smaller in a digital instamatic, pocket type thingy, allowing for much closer images almost down to macro;
2. Cameras like these can also stop down to an F 1.8/1.4 whereas a canon 350 is I would imagine F 4.5 at its lowest.
Having said this and I assume you are shooting in the dark, if the canon 350 was set to everything manually, overide everything and anything that the camera chooses, plus shoot to the far left of exposure, (the camera Always Lies by the way), shoot with exposure indication pushed to the left by reducing the exposure an extra two or three stops on top of this, I am certain that you could get an image better than the instamatic.
PS, one of the biggest myths about cameras is the exposure indicator, most people, understandably, assume that when the exposure indicator is in the middle this is the correct exposure, this is never true, correct exposure is to over and under expose (unless for creativity this is not needed) over and under expose by two to three stops by whatever the camera tells you in most average lighting conditions. In very bright conditions you should over expose by a little more and in very dark conditions you should under expose by two stops at least). reason being that you are not really under or over exposing, what you are doing is over-riding the digital feed back from a computer chip which seeks to reduce everything to neutral grey which is the Exact middle point between the brightest and the darkest possibility. All cameras attempt to pull everything within the light spectrum range from RGB 1.1.1. - 255.255.255 and place it in the 128.128.128 exposure, this is normal and it is the only known way technologically that a camera can work, no matter how advanced, so this is why when an exposure reading needle is in the middle the camera is actually telling you that it has successfully pulled as much of the environment into a percentage range not far from this neutral grey, this is why you can always safely add or reduce your exposure settings by up to three full stops in most situations if the environment is evenly lit.

[Edited on 18-7-2014 by CHRIS25]

[Edited on 18-7-2014 by CHRIS25]

aga - 18-7-2014 at 11:33

Quote:
throw away all automation, you want complete control.

Glad you said that.
I'm buying my first ever digital camera tomorrow, and Full Control sounds like a good plan.

Don't suppose there's a relatively cheap model that springs to mind ?

One that will do 'snaps' and also have an option for manual focus etc ?

CHRIS25 - 18-7-2014 at 14:08

Quote: Originally posted by aga  
Quote:
throw away all automation, you want complete control.

Glad you said that.
I'm buying my first ever digital camera tomorrow, and Full Control sounds like a good plan.

Don't suppose there's a relatively cheap model that springs to mind ?

One that will do 'snaps' and also have an option for manual focus etc ?

sent message

ScienceHideout - 18-7-2014 at 16:20

https://www.youtube.com/watch?v=1vJYJgQN9Ls

^^Interestingly enough, I have a friend in Germany who actually filmed the luminescence of singlet oxygen. If you have any questions, he would be the guy to ask! Perhaps if you have a really specific question I could contact him for you.

violet sin - 18-7-2014 at 18:11

AJKOER, I don't think anything is happening with TCCA or the sodium salts there of. supply or something else perhaps. they are the standard for pool cleanliness where I live, and that won't change any time soon. more people switching to salt pools may have something to do with it. I can buy it by the 50lb tub all, day, long, if I had the inclination to do so.

couple years back I came across a book specifically on singlet oxygen at the thrift store,.. 1$. book 3 of 3 in a series about oxygen by CRC. hansom looking hard bound, tan and burgundy w/ silver accents . cant seem to find the first two, which I would have more use for. it's ~200 mi away at home though so I wouldn't be able to thumb through any time soon.

blogfast25 - 19-7-2014 at 04:14

Quote: Originally posted by aga  
One that will do 'snaps' and also have an option for manual focus etc ?


The Canon 350 e.g. has what they call a 'basic zone' and a 'creative zone'. The basic zone allows a number of preset settings like 'auto', 'portrait', 'close up', 'landscape', 'night' etc. The creative zone allows full control. I haven't gotten to grips with the latter yet but I've got a decent book on it. More study required! :(


[Edited on 19-7-2014 by blogfast25]

AJKOER - 19-7-2014 at 11:24

OK, there is at least eight videos of Singlet oxygen production on YouTube (see https://www.google.com/?gws_rd=ssl#q=youtube+singlet+oxygen ).

I also came across a Patent 4,975,265 ( see http://www.google.com/patents/US4975265 ) that professes some improvement over the classical procedure by spraying a mist of KOH (claimed to be better due to lower viscosity than NaOH) dissolved in H2O2 into a stream of Chlorine gas. The chief reason claimed is that this method reduces solution contact given the ability of water to quickly de-activate Singlet oxygen.

[Edited on 19-7-2014 by AJKOER]

aga - 19-7-2014 at 11:53

Despite the videos, it is interesting to see that you have found a simpler way using commonly available chemicals and equipment.

Your experiment would already have been repeated had i possessed a camera.

Today i got a "Canon PowerShot SX170 IS", so now wading through the plethora of options - seems you can't just press the button.

AJKOER - 19-7-2014 at 12:53

Quote: Originally posted by aga  
Despite the videos, it is interesting to see that you have found a simpler way using commonly available chemicals and equipment.

...........


Not exactly, as 30% H2O2 is not precisely a commonly available chemical. However, one can somewhat easily prepare CaO2 from 3% H2O2, as previously noted on SM.

It is my opinion that Woelen method is better than others, assuming access to the TCCA, as it is highly ionic, little water, acting on the hypochlorite ion (or, HOCl upon hydrolysis of the TCCA), and not so much the Cl2 (which can form strong HOCl with water, but also problematic HCl that needs to be neutralized forming undesired water).

aga - 19-7-2014 at 15:50

Quote:
The funnel has also 2 pieces of ice, some 3% H2O2 and is fitted with a plug (non-organic) to create a slow drip of hydrogen peroxide.

Maybe you're confusing what you've read with what you actually did.

Personally i prefer the AJ that's not blowing smoke.

AJKOER - 20-7-2014 at 19:53

To be clear, I believe the literature pretty much recommends 30% H2O2, which is consistent with the quenching reaction of H2O on singlet oxygen.

My experiment, based on home chemicals, namely 3% H2O2, appears to a more limited extent, is still capable of producing, albeit not easily, some luminescence. The employment of CaO2, as I mentioned, is another route to be investigated, which is based on starting with 3% H2O2.

I got my N2O supply and have been experimenting.

AJKOER - 27-7-2014 at 11:19

Here is an interesting property of N2O, apparently it is much more soluble in alcohol, vegetable oil, ...than in water. This can be used to effect chemical reaction in the lab and at home to infuse flavorings into beverages (see http://www.cookingissues.com/2010/08/11/infusion-profusion-g... . To quote:

"You can infuse flavors into liquor (and water based things, too) almost instantly with nothing more than an iSi Cream Whipper . You can use seeds, herbs, spiced, fruits, cocoa nibs, etc."

The possible explanation per a comment by Dan, to quote:

"Well done! You’ve rediscovered nitrogen cavitation and put it to novel use. Cavitation is used in cell biology labs to gently disrupt cells in a vessel ominously called a “nitrogen bomb” (as the gas here is nitrogen). The usual explanation is close to what you surmised: under pressure, gas penetrates the cells, then forms bubbles to disrupt the cells when the pressure is suddenly released. Your use of the technique looks a lot more interesting than my experiences with it in a lab."

With respect to chemical reactions, as I noted above, N2O is reported to react with singlet D oxygen to form two molecules of nitric oxide:

N2O + O(1D) --> 2 NO

I do recall a source (see Equation 7.5 at http://books.google.com/books?id=N46DxR1xevYC&pg=PA123&a... ) noting a possible second reaction as well:

N2O + O(1D) --> N2 + O2

[Edited on 27-7-2014 by AJKOER]

AJKOER - 31-7-2014 at 04:37

Quote: Originally posted by AJKOER  
Here is an interesting property of N2O, apparently it is much more soluble in alcohol, vegetable oil, ...than in water. This can be used to effect chemical reaction in the lab and at home to infuse flavorings into beverages (see http://www.cookingissues.com/2010/08/11/infusion-profusion-g... . To quote:

"You can infuse flavors into liquor (and water based things, too) almost instantly with nothing more than an iSi Cream Whipper . You can use seeds, herbs, spiced, fruits, cocoa nibs, etc."

....


Apparently, this may be a flavorable idea, but potentially explosive on warming if under pressure! Per an Air Force Research safety report, "Nitrous Oxide Explosive Hazards" by Claude Merrill , available at http://www.dtic.mil/dtic/tr/fulltext/u2/a489459.pdf to quote:

"Super critical extraction explosions were related to organic materials mixed into the primary N2O gas phase. In 1991, Sievers, et. al., reported that a mixture of N2O, 9% ethanol, 0.9% tetraethoxy silane, 0.07% triethyl borate, and 0.07% triethyl phosphate spontaneously exploded under conditions of 143 atmospheres pressure and 40 C. Stainless steel fittings were shattered. Another supercritical N2O event occurred at 680 atmospheres and 80o C while extracting one gram of ground coffee, Raynie, 1993. Power evidenced by shattering of stainless steel fittings could be expected since the quantity of combustible fuel in the N2O would raise kinetic speed of reaction and output energies considerably above that could be produced by N2O monopropellant decomposition. Higher temperatures from a combination of oxidizer fuel reaction and monopropellant reaction would produce acceleration for producing eruptive events. Small scale explosions with N2O containing combustible organic material are evidence that N2O/combustible material mixtures are very hazardous with respect to pure N2O. Since N2O does not have significant monopropellant decomposition until temperatures above 500 C are obtained, reduction of initial reaction temperature with N2O/organic material mixtures to the 40 to 80 C range are particularly daunting. "

Also, to quote:

"Haussmann’s (8) article had interesting observations about behavior of N2O, particularly, interactions when mixed with combustible materials. That is:
- Glycerin is used as a lubricant in pumping N2O and it has frequently been found in N2O storage cylinders.
- Liquid N2O will burn the skin because its lipoid solubility prevents a protective vapor layer from being formed, as with liquid air or carbon dioxide.
- Nitrous oxide is soluble in water and many organic compounds.
- Gas phases of all N2O-fuel mixtures could be exploded by electric fuses.
- Liquid phases of N2O-fuel mixtures exploded only by heavy detonator charges. - Graphite tubes acted more or less as decomposition surfaces for the N2O, and as flameholders rather than reactive fuel.
- Mixtures of N2O and hydrocarbon are monopropellants that are easily transportable explosives, such as, N2O and kerosene.
- Liquid N2O can be compressed by about 40% near its critical temperature under 10.9 MPa (1580 psi) pressure. That is, liquid density was about 0.748 g/ml versus critical temperature density of 0.451 g/ml. Pressure was about 50% higher than critical pressure of 7.3 MPa (1054 psi). "

As voka can be 33 proof or 16% ethanol, assuming no added ice, it may, when the N2O is in a gas phase in a pressurized container, present an explosion hazard if warmed to 40 C . Always very flammable, so smoking around such beverages could start a fire.

More on this topic with other sources in a prior SM thread at http://www.sciencemadness.org/talk/viewthread.php?tid=26967 .

So generally speaking, mixing N2O and organics is a bad idea as the mixture is said to be sensitive to detonation from electro static discharge (ESD) as well. Note, alcohol vapors and N2O always present an explosion hazard with ESD. So, if you insist on trying N2O infused booze, under pressurized conditions, or when your breath is rich in alcohol vapors and N2O, you may not want to pet your cat or wear a sweater, or even get a kiss from someone wearing a sweater, else you may become the 1st reported case of STE (sexually transmitted explosion).

[Edited on 31-7-2014 by AJKOER]

Morgan - 31-7-2014 at 05:26

The other day I was driving right behind a huge tanker truck of liquified N20. I just thought it kind of a funny thing to see.

AJKOER - 31-7-2014 at 09:44

Quote: Originally posted by Morgan  
The other day I was driving right behind a huge tanker truck of liquified N20. I just thought it kind of a funny thing to see.


Morgan:

I hope your final wishes were for creamation, as in the event of an incidence, a N2O explosion are reported to reach 5,000 degrees F :o.

Apparently, the combination of blast damage and extreme heat has proven troubling to accident scene invesitgators (not much left).

[Edited on 31-7-2014 by AJKOER]

sbreheny - 9-4-2019 at 22:27

Very late addition to this thread but this is my singlet O2 video:

https://www.youtube.com/watch?v=c8zsvmgT8g4

nezza - 17-4-2019 at 11:54

It is doable. Here are a couple of pictures of singlet oxygen.

Singlet Oxygen 1.jpg - 253kBSinglet Oxygen 2.jpg - 208kB