Volumetric Nanocrystal Lattice Reconstruction through Dynamic Metal Complex Docking

Vacancies pose a major challengein the production ofhigh-qualitycrystals, particularly at the nanoscale. To address this problem,we report a convenient strategy that involves volumetric lattice reconstructionand dynamic metal complex docking to produce ultrasmall (10 nm) andbright core-shell upconversion nanoparticles (UCNPs). Thisstrategy involves the formation of lanthanide ion-oleic acidcomplexes during postannealing in solution, which effectively removesvacancies in nanocrystals. The removal of vacancies restricts thediffusion of lanthanide sensitizers and emitters within the core,thus minimizing surface quenching. Our volumetric lattice reconstructionstrategy provides fundamental insights into lattice engineering andpresents a general strategy for purifying functional nanocrystalsfor applications in fields such as single-molecule tracking, quantumoptics, energy conversion, and others.