Sprayed Microdroplets Architect a Polyoxometalate Framework

), a valuable POM with broad applications, achieving yields up to 99% in less than a millisecond. Mass spectrometric detection of reactive intermediates unraveled the nucleation mechanism in microdroplets, leading to the formation of polyoxotungstate, which was then further characterized by X-ray crystallography. Empirical observations collectively suggest that rapid solvent evaporation and subsequent enrichment of reactants in the confined volume of microdroplets likely facilitate the growth of the POM through partial solvation at the air-liquid interface.