Surface chemistry controls crystallinity of ZnS nanoparticles
Combined small-angle and high energy wide-angle x-ray scattering measurements of nanoparticle size and structure permit interior strain and disorder to be directly observed in the real-space pair distribution function (PDF). PDF analysis showed that samples of ZnS nanoparticle with similar mean diameters (3.2-3.6 nm) but synthesized and treated differently possess a dramatic range of interior disorder. We used Fourier transform infra-red spectroscopy to detect the surface species and the nature of surface chemical interactions. Our results suggest that there is a direct correlation between the strength of surface-ligand interactions and interior crystallinity.