Nanoscale materials are driving the discovery of physical and chemical phenomena, and providing the basis for cutting-edge technologies that range from low-cost solar cells to targeted gene therapies. At the heart of these advances are controlled chemical synthesis and the development of structure-property relationships. Therefore, for every different nanoparticle synthesized there is the opportunity to uncover new scientific insights and technological capabilities. The next evolution of nanoparticle synthesis will establish rational methods for accessing these materials with an emphasis on controlling surface chemistry and element composition with atomic precision.
The Millstone group works to develop new tools and new insights for nanoparticle synthesis, that allow us to realize this structural control from the bottom-up, ultimately producing nanostructures that incorporate optical, electronic, mechanical, and self-assembly demands into a single nanoparticle architecture. This work is designed to provide not only significant insight into nanoscale reactions and particle properties, but also generate highly tailored material platforms that, together, will allow us to accelerate the translation of nanoparticles into society-shaping technologies.
Impact of Surface Chemistry in Multimetallic Nanoparticle Synthesis and Performance
Metal-ligand chemistry impacts nearly every aspect of nanoparticle formation, physical properties, and util- ity. We develop methods to study and leverage these interactions to produce highly tailored multimetallic nanoparticles with dimensions spanning the nanoscale (1-100 nm). Here, we discuss how metal-ligand interactions may be used to mediate the incorporation and distribution of metals in and on discrete, colloidal nanoparticle substrates, as well as their optoelectronic properties once formed. In particular, we demonstrate that nanopar- ticle ligand chemistry may be used to access previously unobserved mixtures of metals such as continuously tunable Au-Co composition ratios, unique distributions of metals at the surface of a colloidal particle, as well as composition-tunable optoelectronic features. Underpinning these studies are the development of analytical techniques to quantitatively track and ultimately tune the surface chemistry of these nanoparticles in order to create translational insights into the role of nanoparticle surface chemistry in their performance downstream. Together, these results provide mechanistic platforms for the development of nanoscale alloys and other bimetallic structures that we demonstrate are promising for a wide variety of applications ranging from light-driven catalysis to multimodal bioimaging.
Artist: Hava Friedman Logo design: Nick Kotoulas, Jennifer Tran Photography: Nick Kotoulas