A composition including a compound having structural formula (I): Rf is a linear or branched perfluoroalkyl group having 1-3 atoms; n is 0-2; x is 1-3; and Rf′ and Rf″ are (i) independently, a linear or branched perfluoroalkyl group having 1-8 carbon atoms; or (ii) are bonded together to form a ring structure having 4-8 carbon atoms. The composition further includes a hydrocarbon contaminant.