Kui Yu1
Sichuan University1
Colloidal semiconductor binary II-VI metal (M) chalcogenide (E) quantum dots (QDs) have been produced together with magic-size clusters (MSCs), sometimes. For the past 40 years, the QD synthesis has been carried out largely as an empirical art, with limited knowledge about the pre-nucleation stage. Recently, we proposed a two-pathway model to explain the co-production of QDs and MSCs. The LaMer model of the classical nucleation theory (CNT) can be used to understand one pathway, which involves the formation of monomers (Mo) and fragments (Fr) that lead to the nucleation and growth of QDs. The other pathway is multi-step based, which involves the self-assembly of M and E precursors, followed by the M-E covalent bond formation inside each assembly that results in the precursor compound (PC) of MSCs. The PC can transform to ultra-small QDs with enhanced particle yield, binary MSCs, and alloy MSCs. Our studies bring an in-depth understanding of the coproduction of QDs and MSCs and of the prenucleation stage of QDs, contributing to the promotion of the solution synthesis of functional nanomaterials from an empirical art to a science.<br/> <br/><b>References</b><br/>1. Yu, K. et al Transformations Among Colloidal Semiconductor Magic-Size Clusters. <i>Acc. Chem. Res.</i> <b>2021</b>, <i>54</i>, 776−786.<br/>2. Yu, K. et al A Two-pathway model for the evolution of colloidal compound semiconductor quantum dots and magic-size clusters. <i>Adv. Mater. </i><b>2022,</b> <i>34</i>, e2107940.