MAI and MABr are organic salts so it is very sensitive with moisture. You can put it in glove box or any dry place. There will be no degradation in it and can be used for a long time.

As long as you stored it in vacuum and far from intensive UV light exposure it will remain stable and you can use it to fabricate solar cells.

There is some literature handling the stability of iodide perovskite in detail.

Please see for example:Article Review of Recent Progress in Chemical Stability of Perovskit...

Best wishes

Thanks for your valuable answers Prof. Abdelhalim Zekry and

Mr. Rajan K. Singh. I took the XRD of synthesized MAI after 20 days and it is attached here. But the JCPDS data I got is having peak positions from 10 to 40 degrees only. But in my XRD there are peaks after 40 degree also. How can I get the JCPDS data for the whole 2theta values.

There are many impurity peaks are appeared in your MAI XRD. It may be due to degradation or improper phase formation of MAI salt. I am attaching here Pure phase of MAI and one article in which We have mentioned detailed study of synthesis and stability of about MAI salt.

Thank you Mr. Rajan K. Singh. I used the conventional Rota vapour technique for synthesis, at 60 to 70 degree Celsius. Can you suggest any purification method for improving the purity of my material.

You can try 3-4 time washing with diethy ether and dry at 60C for 12h. You can try another method also in which no need of diethy ether treatment.

Good Luck.

Thank you Mr. Rajan K. Singh. I read your method using High vacuum oven. But the temperature controller in our vacuum oven is not working. I will try the purification method that you have mentioned.

ok.

Good Luck.