Hi,
I am using a short (1mm) path length quartz cuvette to obtain UV-Vis absorbance of carbon nanotubes (CNTs) dispersion in various organic solvents.
After filling the cell with the CNTs dispersed in acetylacetone and draining it, I noticed that the CNTs got stuck to the wall of the cuvette. I suspect whatever residue substance that is in the wall of the cuvette binds with the CNTs nicely.
I have tried a whole range of things from warm water + detergent, solvents (ethanol, acetone, NMP), 5M nitric acid, KOH + isopropanol (I know they will etch quartz, but I'm really running out of ideas), but I can't seem to remove the CNTs from the wall of the cuvette.
I am currently considering air annealing the cuvette at 600 - 700°C to remove the CNTs as a last resort. Would this be okay?
Even if the annealing works, I have quite a lot of samples and limited number of quartz cuvettes. High temperature annealing in between samples would be very impractical.
Does anyone have any suggestion for quick cleaning of quartz cuvettes with carbonaceous deposits on the wall?
The small cell size makes it hard for me to physically clean the cuvette. However, I am considering wrapping a lens wiper around a needle and using it to wipe the cuvette. Scratching is a concern of course, but it's better than dirty unusable cuvettes I guess.
Thank you in advanced.