Can some one suggest alternative storage place for photoactive materials like P3HT, PCBM, etc. We dont have sophiscated glove-box environment for storage and solar cell fabrication. It is known solar cell processed inside glove box show drastic improvement in photovoltaic characteristics and power conversion conversion than in open-air conditions. How about keeping active materials inside desiccator under vacuum conditions? Please suggest any alternative storage place.
The problem in working in open air for OPV is the oxidization of the Polymers.
you can always store the materials in a dissicator and under vaccum which will prevent this reaction from accuring.
But when you would like to do some proccessing you will not be able to work in vaccum. Therefore I would advise to work in a chamber with Nitrogen or Argon athmosphere.
You can make a small working area for this in a a regular hood using a schlenk flask for instance.
In this case the only exposer will accur while moving the chip from one compartment to the other which is relatively low.
For the storage of the materials, in the solid state most of them should be OK in air. When you want to be super-careful you can store them in brown glass bottles (or normal bottles wrapped in Al-foil), purge the bottles with nitrogen after every use and keep them in a fridge.
Processing is a different story. As Amit said, you should prepare and spincoat (or whatever you do) your solutions with no oxygen/water present. Since gloveboxes are not readily available you can consider building a kind of enclosure (from perspex maybe?) with two gloves attached to it, like a home-made glovebox. Purge it with nitrogen before every use, while monitoring the humidity inside. It might help, good luck!
personally, I saved P3HT and PCBM in Glovebox, vacuumed desiccator, and air and did not see any difference though. Usually, P3HT and PCBM will not degrade under oxygen if they are kept in dark like amber vial. But, when you deposit films from them, the film should be kept in dry and inert gas environment, otherwise, it will be oxidized and degrade. So no worry for saving the powder in vacuumed desiccator. Just in case, pull vacuum on the blend for around one hour before adding the solvent (chlorobenzene or chloroform or whatever you are using) to make sure there is no water in the solution.
- Badges
- Science topic