Perfluorosulfonic acids

Perfluorosulfonic acids (PFSAs) are chemical compounds of the formula CnF(2n+1)SO3H and thus belong to the family of perfluorinated and polyfluorinated alkyl compounds (PFASs).

Their perfluoroalkyl chain has a highly hydrophobic character.

Perfluorooctanesulfonic acid, for example, has been used in hard chromium plating.

[2] Perfluorooctanesulfonic acid was included in Annex B of the Stockholm Convention in 2009 and subsequently in the EU POPs Regulation.

[3] Perfluorohexanesulfonic acid was included in Annex B of the Stockholm Convention in 2022.