Microdroplets smaller than 20 µm in diameter possess extraordinary chemical reactivity, which underscore their distinctive properties and potential for environmentally friendly production. The droplets could generate hydrogen peroxide (H2O2) without requiring catalysts or applying a voltage, and the rate of H2O2 production is proportional to the surface curvature . Accumulating evidence solidifies the theoretical proposition of an ultrahigh electric field (10 7 V/cm) across the interface, sufficient to induce spontaneous redox reactions.