Gabe's paper, "Real-Time Electroanalytical Measurements of Dynamic Reaction Chemistry Provide Generalizable Mechanistic Considerations for Metal Nanoparticle Synthesis," has been published in the Journal of the American Chemical Society.
In this paper, we demonstrate that open-circuit potential (OCP) measurements of the mixed potential of metal nanoparticle growth solutions are an experimentally accessible yet information-rich method for in situ, time-resolved understanding of the dynamic chemistry that takes place during metal nanoparticle synthesis. We combine OCP measurements of particle growth with point-in-time electron microscopy and elemental analysis to establish the power of OCP measurements even as a stand-alone approach. We anticipate that this approach will be broadly generalizable across other metals, metal oxides, semiconductors, and other synthetic inorganic materials.
Through detailed analysis of these OCP measurements, we reveal the importance of reagent depletion around seed particles and diffusion early in the nanoparticle growth process in determining the overall reaction kinetics that direct shape evolution. We establish the relationship between the measured mixed solution potential and the metal ion reduction rate laws for a series of kinetically-controlled particle shapes. Additionally, we use OCP measurements to readily distinguish between kinetic and surface passivation control of nanoparticle shape and between seeded growth and homogeneous nucleation in situ and in real time. All of the above will accelerate understanding of outstanding mechanistic questions in nanomaterials synthesis and facilitate directed synthesis design.
Congratulations to Gabe and co-author Abby!
We are grateful to the National Science Foundation for supporting this work.