Dear Aditi,

If you are referring to the material used to record the FTIR spectra, then I would recommend KBr pellets. You can get the full range of useful vibrations using KBr. See for example one of our articles with a FTIR discussion on mesoporous aluminosilicates: DOI:10.1016/j.micromeso.2013.08.018.

KBr is the best for analysis of FTIR. mix your material and KBr salt (1:10) properly in pestle and make pellet. KBr is hydroscopic in nature so pallets should be stored in dry place.   

Hello Rajan,

Was that 1:10 by weight?

-Abhinav