Thermal switch of oscillation frequency in Belousov-Zhabotinsky liquid marbles (1901.03961v1)

Abstract: External control of oscillation dynamics in the Belousov-Zhabotinsky reaction is important for many applications including encoding computing schemes. When considering the BZ reaction there are limited studies dealing with thermal cycling, particularly cooling, for external control. Recently, liquid marbles (LMs) have been demonstrated as a means of confining the Belousov-Zhabotinsky reaction in a system containing a solid-liquid interface. BZ LMs were prepared by rolling 50 {\mu}l droplets in polyethylene (PE) powder. Oscillations of electrical potential differences within the marble were recorded by inserting a pair of electrodes through the LM powder coating into the BZ solution core. Electrical potential differences of up to 100mV were observed with an average period of oscillation ca. 44 s. BZ LMs were subsequently frozen to -1oC to observe changes in the frequency of electrical potential oscillations. The frequency of oscillations reduced upon freezing to 11mHz cf. 23mHz at ambient temperature. The oscillation frequency of the frozen BZ LM returned to 23mHz upon warming to ambient temperature. Several cycles of frequency fluctuations were able to be achieved.