Floquet States of Chemoselective AC Electrosynthesis

Alternating currents (ACs) offer precise synthetic control through potential modulation, yet theoretical understanding of the underlying mechanisms remains scarce as the simulated outcomes are generally reproducible by direct currents (DCs). Further computational explorations of the chemical space are also limited by the multiscale nature of the electrochemical dynamics. In this work, we propose to interpret AC-electrolytic outcomes as Floquet states. This narrows the simulation domain to a single AC period, which reduces computational costs, while decomposing the coupled electrochemical kinetics into interpretable subprocesses, providing physical intuition for future synthetic designs. Notably, we explore how non-electrochemical steps may create Floquet AC outcomes with no DC analogues, strengthening the role of AC in electrosynthesis. Experimentally, we demonstrate how AC facilitates mass transport for selective methyl thiophene-2-carboxylate electroreduction via coarse-graining effects captured in the Floquet states. Ultimately, given the success of Floquet engineering in quantum condensed matter systems and photonic architectures, we hope to inspire similar programmes in AC electrochemistry.