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How to chemically remove silane molecules which are covalently...
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+ Solvent effect
+ Silanes
+ Chemical bonding
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Lasith S. Kariyawasam
How to chemically remove silane molecules which are covalently...
Hi Hariharan, Xaviers idea of using 29Si MAS NMR is a very good one! you could also check the remaining organic content of your rinsed samples by elemental analysis. If you just want to remove the organic stuff from the surface of your silica particles I think it's indeed best to do it on an acid and oxidizing way as you intended - have you tried hot concentrated HNO3 for this purpose, yet? Best regards and good luck
Hi Hariharan, Xaviers idea of using 29Si MAS NMR is a very good one! you could also check the remaining organic content of your rinsed samples by elemental analysis. If you just want to remove the organic stuff from the surface of your silica particles I think it's indeed best to do it on an acid and oxidizing way as you intended - have you tried hot concentrated HNO3 for this purpose, yet? Best regards and good luck
Dr. Sujoy Biswas Try out Piranha solutions which are generally used to remove organic residues from substrates. Usually, piranha solution is a 3:1 mixture of sulfuric acid and 30% hydrogen peroxide. Caution: Piranha is corrosive. Reference: https://ehs.princeton.edu/book/export/html/513
Dr. Sujoy Biswas Try out Piranha solutions which are generally used to remove organic residues from substrates. Usually, piranha solution is a 3:1 mixture of sulfuric acid and 30% hydrogen peroxide. Caution: Piranha is corrosive. Reference: https://ehs.princeton.edu/book/export/html/513
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
As Alexander stated all of the mentioned oxidising media will remove the organyl part of the silane the silicon is covalently bonded. Only HF will remove each the Si-surface which I would not suggest. But keep in mind that the molecule is not removed (it will be fragmented). You can also use temperature (furnace or burning) or UV-irradiation.
As Alexander stated all of the mentioned oxidising media will remove the organyl part of the silane the silicon is covalently bonded. Only HF will remove each the Si-surface which I would not suggest. But keep in mind that the molecule is not removed (it will be fragmented). You can also use temperature (furnace or burning) or UV-irradiation.
@Kampfe I havn't used Conc. HNO3 yet. I was previously using H2O2+H2SO4 or H2CrO4 (sulphochromic acid). I am sure that these strong acids can remove organic compound which adhere on the glass substrate, my doubt is whether these acids are good for removing covalently bound silane molecules for the glass surfaces.
@Kampfe I havn't used Conc. HNO3 yet. I was previously using H2O2+H2SO4 or H2CrO4 (sulphochromic acid). I am sure that these strong acids can remove organic compound which adhere on the glass substrate, my doubt is whether these acids are good for removing covalently bound silane molecules for the glass surfaces.
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
Hi Hariharan,
Xaviers idea of using 29Si MAS NMR is a very good one! you could also check the remaining organic content of your rinsed samples by elemental analysis. If you just want to remove the organic stuff from the surface of your silica particles I think it's indeed best to do it on an acid and oxidizing way as you intended - have you tried hot concentrated HNO3 for this purpose, yet?
Best regards and good luck
Hi Hariharan,
Xaviers idea of using 29Si MAS NMR is a very good one! you could also check the remaining organic content of your rinsed samples by elemental analysis. If you just want to remove the organic stuff from the surface of your silica particles I think it's indeed best to do it on an acid and oxidizing way as you intended - have you tried hot concentrated HNO3 for this purpose, yet?
Best regards and good luck
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@Schmitt, Currently, I introduce the silane bound silica surface to butane flame. In this process the covalently bound silane is oxidized.
@Schmitt, Currently, I introduce the silane bound silica surface to butane flame. In this process the covalently bound silane is oxidized.
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I want to remove Triethylsilane (TES) from Quartz surface using acetone and followed by nitric acid wash but it is not removed. Can any person help?
I want to remove Triethylsilane (TES) from Quartz surface using acetone and followed by nitric acid wash but it is not removed. Can any person help?
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Dr. Sujoy Biswas Try out Piranha solutions which are generally used to remove organic residues from substrates. Usually, piranha solution is a 3:1 mixture of sulfuric acid and 30% hydrogen peroxide.
Caution: Piranha is corrosive. Reference: https://ehs.princeton.edu/book/export/html/513
Dr. Sujoy Biswas Try out Piranha solutions which are generally used to remove organic residues from substrates. Usually, piranha solution is a 3:1 mixture of sulfuric acid and 30% hydrogen peroxide.
Caution: Piranha is corrosive. Reference: https://ehs.princeton.edu/book/export/html/513
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Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
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@ Hariharan How did you remove the APTES finally ?
@ Hariharan How did you remove the APTES finally ?
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THanks Kampfe :)
THanks Kampfe :)
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Thanks
Thanks
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As Alexander stated all of the mentioned oxidising media will remove the organyl part of the silane the silicon is covalently bonded. Only HF will remove each the Si-surface which I would not suggest. But keep in mind that the molecule is not removed (it will be fragmented). You can also use temperature (furnace or burning) or UV-irradiation.
As Alexander stated all of the mentioned oxidising media will remove the organyl part of the silane the silicon is covalently bonded. Only HF will remove each the Si-surface which I would not suggest. But keep in mind that the molecule is not removed (it will be fragmented). You can also use temperature (furnace or burning) or UV-irradiation.
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@Kampfe I havn't used Conc. HNO3 yet. I was previously using H2O2+H2SO4 or H2CrO4 (sulphochromic acid). I am sure that these strong acids can remove organic compound which adhere on the glass substrate, my doubt is whether these acids are good for removing covalently bound silane molecules for the glass surfaces.
@Kampfe I havn't used Conc. HNO3 yet. I was previously using H2O2+H2SO4 or H2CrO4 (sulphochromic acid). I am sure that these strong acids can remove organic compound which adhere on the glass substrate, my doubt is whether these acids are good for removing covalently bound silane molecules for the glass surfaces.
More
VOTE
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
Hi Hariharan, your right, I'm also sure that the acids you already used remove most of the organic stuff. In case of sulphochromic acid I'd be afraid that there will remain some Cr in your particles what might be disadvantageous for your further chemistry. Hot and concentrate nitric acid will also attack the organic part of a trimethylsilyl group, leaving behind a "new born" trihydroxysilyl group. However, I guess this group is what you might look for in terms of resilylation. The only thing is that while applying this method your particle grows by a two atom layer each cycle. But this is the case for the acids you mentioned, too. Any traces of HNO3 may afterwards be removed more easily, as HNO3 is less viscous and more volatile than H2SO4 and contains no Cr. Have fun with silicon chemistry! Best Regards
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