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Antimony sulfoiodide (SbSI) exhibits very interesting properties including high photoconductivity, ferroelectricity, and piezoelectricity and can be used in solar cells to increase the efficiency (light harvesting).
On the picture: Antimony sulfoiodide (SbSI) nanorods solution. ... See MoreSee Less
Selenium doped borate glass.
Barium borate glass doped with 3 mol% Selenium (using Barium Selenite). A fraction of it evaporated during melting - I needed to use a mask for safety during handling. It looks very similar to the sulfur doped glass but more brownish. ... See MoreSee Less
Hafnium + Sulfur doped borate glass ingot.
This is the same red glass I described a few weeks before. In the meantime I resolved most of the mystery of the origin of the color which comes actually from sulfur (sulfides). The hafnium doping (3 mol%) has no visible effect on the color but could occur as HfS2 (brown-red).
I noticed a smell of H2S when I ground and polished this glass. ... See MoreSee Less
Iodine doped glass.
It is possible to incorporate the highly volatile iodine into glass. Normally every attempt to try this is doomed to failure. The iodine escapes long before the glass is forming. The literature suggests to use Alkali rich glasses and add iodine or sodium iodide to glass powders which is being hot pressed @ 20 - 25 tons in a sealed platinum crucible before melting.
I tried a different way by adding high melting anhydrous rare earth triiodides to the glass mixture hoping that it would survive a few minutes in the liquid glass before evaporating. Seems an easy task, but first I needed to synthesize the iodides (200€/g was a bit too expensive for glass experiments)😉. Here is the result: The added GdI3 (in excess!) caused a slight lemon yellow coloring. ... See MoreSee Less
Update: I found out that the color does not come from Hf metal or lower Hf oxides or any other heavy metal. I made a series of glasses using the same compounds but with no addition of Hafnium. Changes in temperature and processing time resulted in different shading / color of the glass up to colorless species. Further investigation is needed 😎 ... See MoreSee Less
Please do elaborate 🔥💎👍
Hafnium doped borate glass.
Another 'what-the-hell..' glass!! 😲 Hafnium doped borate glass should be colorless. In this case the hafnium appears in the +4 state.
I tried to get a lower Hf oxidation state and was quite surprised that the colorless liquid glass turned almost black within a few seconds and after cooling I got these mind-blowing blood red beads.
My first thought was, that this is Hf3+ or even Hf2+ but the color change by cooling reminded me of the reaction with gold ruby and Tellurium ruby glass, i.e. Hafnium nano particles!? Is this another example?
But the most surprising was the deep red luminescence under 365nm UV. I didn't find any scientific articles or mentions about it.🧐🤓 ... See MoreSee Less
Obviously you had a reduction reaction there, either to nanoparticles of Hf or somehow an inferior oxidation state. What do you think had such a strong reducing power in your initial composition, what was your maximum temperature you went to?
Another "surprise" glass: Rhenium doped Barium phosphate glass. I expected a colorless or pale yellow glass which it was when still hot. On cooling the color changed to pale blue which cannot be the +7 state of Re as stated in the literature!? ... See MoreSee Less
This effect only occurred at higher temperatures when phosphate glasses have reducing properties. I did not manage to get more than these two beads. Re is horrible as dopant, it also evaporates relatively fast.
I think that the oxidation state of the rhenium compound does not matter in this case. I used Re powder and NH4ReO4 with same result.
NH4ReO4 will be reduced to Re nanoparticles immediately.
Those are gorgeous! It depends if you use an oxidative or reducing mixture to produce the doped barium phosphate. Also it depends what Re compound you have used..... I am planning to try Re in 3, 5, 6 and 7 oxidation state in different starting mixtures soon.
Chromium 3+ doped Large Phosphate glass beads.
High melting point Sodium Aluminum Zinc phosphate glass doped with 0.15 mol% Cr2O3. The glass is very durable and chemically resistant. ... See MoreSee Less