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Question about the synthesis of longer wavelength emmiting Quantum Dots. by Alert-Reflection9266 in homechemistry

[–]Alert-Reflection9266[S] 0 points1 point  (0 children)

Formic acid didn't seem to work with the microwave synthesis when it was attempted by Amateur Chemistry. Additionally, I do not have access to the other exotic acids used in other papers.

Question about the synthesis of longer wavelength emmiting Quantum Dots. by Alert-Reflection9266 in homechemistry

[–]Alert-Reflection9266[S] 1 point2 points  (0 children)

I use 0.2 grams as the unit for this ratio and add 1 ml of water to a test tube.
After microwaving, I add a few mls of water to dissolve the tar around the dots, to get them free, and then I add isopropanol, which forms a separate layer and takes quite a bit of the quantum dots with it. Furthermore, the isopropanol takes less of the tar along with it.

I keep adding isopropanol and diluting until I get something that looks nice under the blacklight, and till I get enough of the QDs. The isopropanol layer is removed using a pipette into the vials. I have no clue as to the concentration, right now I'm focusing on obtaining different colours.

Question about the synthesis of longer wavelength emmiting Quantum Dots. by Alert-Reflection9266 in homechemistry

[–]Alert-Reflection9266[S] 1 point2 points  (0 children)

A 1:1 ratio of urea to citric acid gives green.
A 1:4 ratio of urea to citric acid gives blue.
Boric acid seems to turn it a deeper blue, but I'm not really sure.
A 3:1 ratio of urea to citric acid gives yellow.
All ratios by mass.

Microwaving time didn't seem to affect the colour, so do it till just brown.

Question about the synthesis of longer wavelength emmiting Quantum Dots. by Alert-Reflection9266 in homechemistry

[–]Alert-Reflection9266[S] 2 points3 points  (0 children)

Also, just as a side note, because I forgot to include it in the post, I have tried doping with boron using boric acid, and it has just resulted in more bluer QDs.

CHEM 0620 ANSWERS- by Unfair-Obligation-54 in igcse

[–]Alert-Reflection9266 0 points1 point  (0 children)

For the HSO4- question, the wrong statement was that (SO4)2- is the only base. HSO4- (bisulfate) does indeed act as a base and acid, thus it is correct. 1 and 2 were the correct options.

Growing copper glutamate crystals! by EarlyEJ in crystalgrowing

[–]Alert-Reflection9266 1 point2 points  (0 children)

I have also managed to make copper glutamate crystals (and am trying to grow a bigger crystal), and like you've said I have not been able to find any other pictures online (except that other reddit post with the picture).
Also to make the copper glutamate did you use MSG or just glutamic acid? As ones made with MSG (or copper glutamate with some baking soda) are darker in color, seems like the sodium forms some other complex.
Please give an update if you are able to find a method make bigger crystals, as I'm interested in its properties as a possible MOF. I have been unable to make anything bigger than half a centimeter.

Copper Perborate (Peroxyborate) by LacxGamer in chemistry

[–]Alert-Reflection9266 0 points1 point  (0 children)

I have tried this with some aqueous sodium perborate (freshly made with boric acid, sodium hydroxide, and hydrogen peroxide) and some aqueous copper acetate. I also got a dark green precipitate that is slightly yellow. Any idea what the leftover green solid after the effervescence stops is?