Patent ID: 8168830

Claim:
A diionic liquid salt comprising at least one di-cation of the formula: A-B-A′ and at least one counter anion; wherein A and A′ are mono-cationic groups independently selected from the group consisting of protonated tertiary amine of formula —[N(R) 2 H] + , optionally substituted imidazolium, and thionium of formula —[S(R) 2 ] + , wherein A and A′ are not the same; each R is independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, phenyl, and benzyl; and bridging group, B, is an optionally substituted C 4 -C 40 hydrocarbon backbone, wherein the hydrocarbon backbone optionally contains, in addition to carbon and hydrogen atoms, at least one heteroatom selected from the group consisting of nitrogen, oxygen, sulfur, and silicon.