CH3CN, complex was well dispersed and displayed relative weaker
fluorescence intensity of their “solution” state. With water volume
fraction increasing from 0 to 90%, the emission intensity of about
504 nm enhanced gradually exhibiting typical AIEE characters. As
a contrast, only HNA without addition of CN− did not show any
AIEE effect (Supplementary data, Fig. S10). This AIEE effect could be
explained by the blocking of the nonradiative intramolecular rotation
decay of excited molecules through the formation of HNA–CN−
complex. The blue shift of the emission band with the increasing
of water volume fraction indicated the H-aggregates [39,40].
Such kind of phenomenon was also found in other salicylaldehyde
Schiff base compound [40,41]. To provide further evidence, particle
size analysis was performed and the result indicated the formation
of nano-scaled aggregates with an average particle diameter
Scheme 2.