Abstract
The interfacial along with bulk characteristics of the aqueous solutions of ILs with dissimilar cationic head group viz. 1-dodecyl-3-methylimidazolium bromide ([C
12
mim][Br]), and N-dodecyl-N-methylmorpholinium bromide ([Mor
1,12
][Br]) in the absence and the presence of an amino acid L-Methionine as an external additive have been examined by electrical conductivity, UV-Visible, surface tension, and DLS measurements. The CMC values, and the lowest maximum surface excess concentration (Г
max
) achieved from all three techniques, and surface tension measurements respectively displayed more surface activity of the [C
12
mim][Br] than the [Mor
1,12
][Br]. Also, the morpholinium head group is less hazardous than imidazolium, it can be utilised to design ILs that are greener, mainly in combination with polar, small, and non-toxic side chains and anions.
Image 1
1-dodecyl-3-methylimidazolium bromide, N-dodecyl-N-Methylmorpholinium bromide, L-methionine, CMC, Electrical conductivity, Surface tension.