nezza
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Infra red blocking chemicals
A while ago someone posted asking for information on chemicals which block infra red. I have been looking at a few spectra lately and copper (II) in
aqueous solution looked a good candidate. I photographed an approximatelty 0.2M solution of copper and nickel sulphate along with water to test this
theory. The two pictures are attached and indeed hexaaquo copper (II) does seem a good blocker for infra red.
 
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phlogiston
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I don't recall the post with that question, but depending on what it was intended for it might be helpful if you could post the absorbtion spectra if
you already have them.
Nice picture. How was it made (lightsource, any filters, detection?
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"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
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nezza
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The pictures were taken by daylight (overcast). The infra red image with a 720nm filter. Both Canon cameras, the infra red image from a modified EOS
10D and the visible one with an EOS 7D using a macro lens.
I have attached an image of the measured absorption spectra of various copper complexes, aquo, Ammonia (NH3) and Ethylenediamine (en). The light
source I use for spectrometry is only really useable between 400 & 700 nm so the infra red absorptivity was guessed by looking at the curves.
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Bezaleel
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That's a beautiful plot you have there, Nezza!
It seems as if the aquo-complex only has as single broad peak, whereas the (NH3)- and (en)-complexes have a peak with a left and right shoulder (or
(en) with two right shoulders if you will).
I infer that you used (en) in excess, correct? If so, I would be interested to see what the bis(en) complex would show - would it indeed have both the
peak from the aquo complex and also one or more peaks from the (en) complex?
Edit: how did you measure these spectra?
[Edited on 30-5-2014 by Bezaleel]
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PHILOU Zrealone
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Good to know to effectively catch the heat from the sun in the case of solar-water heating systems....
A mix of excess Cu(2+) and non excess H2N-CH2-CH2-NH2 will cover all the light field between 500-750 nm.
Ammonia complex will be more troubles because less stable and upon heating NH3 gas might pressurize the container.
The presence of the salts will increase the boiling point and lower the freezing point of the calori-porter fluid.
So water, Cu(2+), EDA in such solar pannels can go into a heat exchanger to give the stored sun heat to water for sanitary use (douch, bath, heating
circuit)...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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DraconicAcid
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Have you tried the EDTA complex? Ethylenediamine will still evaporate; EDTA will not.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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unionised
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I realise this isn't a very "scientific" question, but how much can you dilute the aqueous copper solution before it stops looking "black" in the IR?
Incidentally, on a related note a dilute solution of ferric chloride does a good job of blocking UV.
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