Toward Scable and Autonomous Synthesis of Colloidal Metal Nanocrystals

Colloidal metal nanocrystals have found widespread use in a broad range of applications, and therfe is an urgent call for scalable and potentially autonomous synthesis. The first step is to make the synthesis reliable, reproducible, and predictable. Recent studies suggest that reduction kinetics play an important role in determining the outcome of a colloidal synthesis of metal nanocrystals. The reduction rate not only controls the internal defect structure, including single-crystal, singly-twinned, multiply-twinned, and stacking-fault lined, of a seed formed in the nucleation step but also dictates the growth pattern (symmetric vs. asymmetric) or mode (island vs. layer-by-layer) of the seed in the following steps. In this talk, I will start with a brief introduction to our recent success in quantifying the kinetic parameters, including the rate constants and activation energies, for a number of systems and then illustrate how this knowledge can be applied to deepen our understanding of the nucleation and growth processes, moving toward the ultimate goal of achieving deterministic and predictable synthesis, together with an easy and quantitative control. The quantitative measure and control allow us to precisely and reproducibly tailor the properties of colloidal metal nanocrystals for a broad range of applications in catalysis, photonics, electronics, energy conversion, sensing, imaging, and biomedicine.