posted on 2023-11-29, 10:03authored byYash B. Barot, Vivek Anand, Roli Mishra
A highly fluorescent, red-emitting
rhodamine-based imidazolium
ionic liquid (RhB-IL) was synthesized, and its structure was extensively
verified using various spectroscopic techniques. The novel molecule
showed exceptional selectivity toward Hg2+ ions over other
competitive metal ions. Additionally, inspired by the solution results,
a paper-based device was fabricated by embedding RhB-IL on paper strips
and tested for the on-site detection of Hg2+ ions using
a portable UV light source. Significantly, the device displayed excellent
PL sensing behavior toward Hg2+ with a detection limit
of 0.21 nM. In addition, RhB-IL showed the phenomena of aggregation-induced
enhanced emission. In fact, when compared to the pure THF solution
of RhB-IL, a remarkable 7.7-fold increase in PL intensity was seen
for the 90% water fraction. Evidently, this is the first report of
a paper-based Hg2+ detection system that uses a red fluorescent
ionic liquid.