Chemistry Reference
In-Depth Information
Fig. 6.11
Scheme for light
controlled release of bromine.
Silver bromide colloids are
included in the aqueous phase
which are degenerated by light
to release bromine, which
participates in the reaction
with pristine mono-olein
particularly the near fields as we have shown. The chemical tuning to drive the
droplets is highly nonlinear, thus making control rather challenging. Further due to
this reason, the precise conditions which initiate the motion are not easily accessible.
As we also discussed, enhanced control over the motion mechanism can allow us to
tune the 'squirmer mode'. Therefore, as a next step, it is planned to replace the B-Z
reaction mixture inside the droplets with an aqueous suspension of silver bromide
(AgBr) colloids as shown in Fig.
6.11
. As the light sensitivity of AgBr is well known
from photographic techniques, it might be possible to trigger the controlled release
of bromine from within the droplets by light of a suitable wavelength. Therefore, in
addition to finding the precise conditions to initiate motion, we might be also able to
tune the 'activity' of the droplet squirmers in a light dependant manner. Such control
will be very crucial in studying the properties of the droplet squirmers in greater
detail.
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