From Microcurrents to Macrodynamics: Harnessing Mixed Potentials for Large, Tunable Acceleration of Belousov-Zhabotinsky Oscillations.

Chemical oscillators such as the Belousov-Zhabotinsky (BZ) reaction offer a promising foundation for energy-efficient, biologically inspired chemical information processing. While optical and mechanical manipulation of BZ has been extensively studied, electrochemical control has remained largely elusive and lacks fundamental understanding, in spite of its superior energy efficiency. Here, we investigate how a platinum electrode influences the dynamics of a ruthenium-catalyzed BZ reaction. We observe a pronounced acceleration of the oscillation frequency that scales with the electrode's surface-to-solution-volume ratio. In addition, we demonstrate that small DC currents (<0.4 mA) further modulate the effect up to a full recovery of the natural period. To explain these findings, we develop a quantitative model based on mixed-potential theory, which accurately captures the observed behavior. This framework reveals how the low-volume electrochemical conversion of molecules at the electrode's surface gets amplified by the chemistry and finally causes a pronounced impact on the entire system. This surprising effect, controllable through small applied currents, offers new strategies for designing programmable chemical systems for sensing and computing applications.