An Iodide-Mediated Microdroplet for Efficient Ozone Decomposition

Microdroplet chemistry offers a promising platform for advancing green chemical processes; however, its limited reaction efficiency has restricted practical applications. Herein, we report a scalable iodide-mediated microdroplet system that markedly enhances stability and rate. The iodide-mediated microdroplet system (0.1 wt %) can achieve 100% ozone (O3) decomposition at the gas–liquid interface for 120 h and exhibits continuous and stable characteristics. Experiments proved that compared with bulk solution, I– enrichment and strong O3 affinity at microdroplet interfaces promote the accumulation of reactants and stabilize transition states. Moreover, the strong interfacial electric field induces hydroxide dissociation and drives electron-mediated regeneration of I– from iodine species, thereby sustaining continuous O3 reduction. Compared with the spray reactor, the iodide-mediated microdroplet reactor achieves a 100% O3 conversion, above 5-fold longer operational stability, 8.0% cost, and 10.4% energy consumption. Life cycle assessment further confirms its superior environmental and economic performance. This work provides a mechanistic understanding of the iodide-driven interfacial redox reaction and offers a scalable, green approach for O3 purification.