D4RR3N
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Boron in Nitric Oxide B+NO
If powder Boron was heated in a sealed container under Nitric oxide gas what would be the result of the experiment?
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not_important
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If the boron was quite finely powdered and you heated it hot enough, say orange heat, you'd get B2O3 and if there is an excess of boron some boron
nitride will be formed.
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D4RR3N
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So essentially you would end up with an oxide of Boron and a nitrogen gas atmosphere leftover, I was thinking you might get a small quantity of BNO
forming also (boron oxynitride).
[Edited on 31-12-2009 by D4RR3N]
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not_important
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You may get some, but I doubt it's a good way to the pure material.
What about the boric acid - ammonia route? see doi:10.1016/0925-8388(95)01532-9 That's also a route to BN ( http://www.a-m.de/deutsch/literatur/cb0694.htm ) so the conditions need to be controlled.
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D4RR3N
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Boron Oxynitride (BNO) has little uses at present but has been produced for use in new capacitors in very thin layers. I would like to make a few
grams of BNO but not sure how to go about it.
Yes I did think of using boric acid crystals. Heating the boric acid which will convert it to an oxide of boron and then reacting that with Nitric
oxide or Nitrus oxide. Not sure what is the easiest and cheapest method at present.
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not_important
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boric oxide isn't too likely to react with nitrogen oxides. The boric acid/ammonia method is effectively a dehydration B(OH)3 + N(H)3 => BN + 3
H2O, reacting nitrogen oxides with B2O3 requires forming oxygen or higher oxides of nitrogen which to me seems unlikely considering boron's attraction
to oxygen.
Another compound used is trimethyl borate, B(OMe)3, and ammonia; although this is better for making BN as the intermediate states contain a fair
amount of carbon as well as oxygen. Treating an intermediate B-N-O-C substance with nitrogen oxides might selectively remove the carbon, but that
seems more complex than the B(OH)3 + NH3 routes.
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D4RR3N
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I was thinking of using high temperatures with the gas reactions whether it be using boric acid or elemental boron reacting at temperature with an
oxide of nitrogen gas.
Ammonia + Boric acid sounds like a better plan. I'm assuming that it will form boron nitride BN and then I'm going to have to oxidise that somehow?
I could also start with pure boron nitride BN powder but its not very reactive.
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JohnWW
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BN occurs in two major crystalline forms (besides amorphous), containing alternate N (positively-charged) and B (negatively-charged) atoms: (a) one
like graphite, hexagonal, existing in an infinite 2-dimensional hexagonal mesh which forms layers and which is aromatic and electrically-conducting,
and can be used as a lubricant and made into fibers and nanotubes like graphite; and the other is an infinite 3-dimensional single-bonded covalent
structure like diamond, cubic holosymmetric, requiring very high pressures to create, which has possible uses as a substitute for diamond (both as
gems and as an abrasive) and as a semiconductor (either doped or with a slight excess of either B or N) with a high band gap voltage. There is also a
wurzite-like cubic form, which again is structurally similar to a rare carbon mineral.
See: http://en.wikipedia.org/wiki/Boron_nitride http://www.azom.com/Details.asp?ArticleID=78 http://www.britannica.com/EBchecked/topic/74404/boron-nitrid... http://www.bn.saint-gobain.com/
It should also exist as an aromatic molecular analog of fullerene, C60, with the formula B30N30, called azaborafullerene, but it is not clear whether
it has been actually synthesized, although it has been theoretically considered. However, a difficulty is that it would contain, around the twelve
5-membered rings, N-N and B-B bonds in spite of the like charges on each of these pairs. See e.g. http://www.springerlink.com/index/A4H757W326238T2Q.pdf , http://pubs.acs.org/doi/abs/10.1021/ja00042a032 , http://doi.wiley.com/10.1002/qua.560520120 , http://www.jstor.org/stable/54133 (someone please retrieve these) , http://ww.chem.ccu.edu.tw/~sll/publications/118.pdf , http://www.journal-spqeo.org.ua/users/pdf/n4_2000/545_3_00.p... , http://www.iop.org/EJ/article/1742-6596/176/1/012014/jpconf9... , http://joi.jlc.jst.go.jp/JST.JSTAGE/bcsj/73.1791?from=Google , http://ir.lib.nctu.edu.tw/dspace/bitstream/987654321/10022/1...
However, "BNO", which is likely to exist with a range of compositions and be non-stoichiometric, is of less use, except as a ceramic material, usually
prepared as a thin film by RF sputtering, and abrasive; see http://linkinghub.elsevier.com/retrieve/pii/S092596350800123... (someone please retrieve this article).
[Edited on 1-1-10 by JohnWW]
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not_important
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doi:10.1016/0925-8388(95)01532-9 talks about BNO directly starting with NH3 and B(OH)3, it's a step on the path to straight BN. High temperatures
are generally used, 600 to 1200 C. Also http://dx.doi.org/10.1149/1.1810432 for thin films of fluorine doped BNO
BNO is non-stoichiometric, getting close to BNO requires fairly tight control of reaction conditions. Researchers going after films form them
directly as the composition of the bulk material changes on further heating.
Also see your earlier thread http://www.sciencemadness.org/talk/viewthread.php?tid=10500
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D4RR3N
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Yes this is something I looked into a while back but never found a method of making sufficient quantity's of BNO, most methods described are for
producing thin films on silicon wafers. Do you think it possible to produce it in any quantity?
My consideration keeps getting drawn back to Boron powder sealed in a container at high temperature under NO gas, I don't see why it wouldn't have the
same probability of producing BNO as the ammonia + Boric acid method (and how would you remove the hydrogen introduced by the Ammonia)
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not_important
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The conditions for the reaction of boron and nitrogen appear to be a bit toasty - 1100 C and higher, At these temperatures I don't think there would
be much difference between starting with a nitrogen oxide vs a mix of N2 and O2.
Everthing I saw starts with B(OH)3 or B2O3 plus a reduced nitrogen compound - ammonia, urea, ammonium salts. Borates plus ammonium salts have also
been used to make BN, for example borax and ammonium chloride or sulfate. This is suggestive that the direct combination of boron is either not very
productive, or that it is much more of a bother and/or expensive than starting with B2O3 or its simple derivatives.
The references that I saw, some in abstract form only, are suggestive that BNO is a transitional phase between BN and B2O3 and not stable in true bulk
form, Fast quenching might yield a BNO phase, but likely unstable to being worked or heated.
Those references also suggest to me that you will need access to proper insrumentation to determine if you have BNO or a mechanical mixture.
Significant percentages of C, Si, Al, P, Ti, and so on, appear to yield stable phases high in B+N+O; however the amount of the other elements is such
that the product can not properly be called "BNO".
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D4RR3N
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If BNO has been considered as a dielectric in capacitors I would have thought it must be stable otherwise such capacitors would have a short shelf
life.
Yes as a molecule it looks like it is a bit of a nightmare to produce in any quantity!
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not_important
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A number of materials are stable in thin layers or small particles yet unstable in bulk. Silicon monoxide is one such, it exists in the gas phase and
as thing films or nanoparticles, in bulk it soon becomes a mixture of Si and SiO2.
The thin layer can prevent sufficient amounts of one or more of the more alternative phases from forming, leaving the base compound in a metastable
state. (remember that diamond is metastable at STP) In some case the energetics are such that the phase is stable in small sections, and there is the
interaction with the materials it touches to consider as well.
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