University of California, Berkeley
Molecular Design of Solids and Surfaces
Novel materials will be central to solving some of the greatest challenges facing society in the 21st century, including energy storage and utilization, chemical separations, water purification, and targeted drug delivery. This talk will focus on strategies for bringing molecular-level control to the design of two classes of materials. The first part of this talk will discuss a strategy for bringing molecular-level precision to heterogenous active sites for electrocatalysis. I will present a class of materials that features a conjugated aromatic linkage that gives rise to an unprecedented level of electronic coupling between a molecular species and a graphitic electrode. Electrochemical and spectroscopic data indicate that these graphite-conjugated catalysts (GCCs) do not behave like their molecular analogues but rather as metallic active sites with molecular definition, making GCCs a rich platform for controlling heterogeneous catalysis at the molecular level. The second part of this talk will focus on synthetic strategies that enable molecular-level control over the materials properties of metal–organic framework (MOF) crystals. Addition of coordination modulators during the synthesis of metal–organic frameworks is a common approach for controlling crystal properties, including size, shape, phase, and surface chemistry. However, coordination modulators can simultaneously affect the protonation state of the linker during synthesis, which can also significantly influence crystal properties, making it challenging to extract synthetic design principles. I will discuss the use of non-coordinating buffers to independently control the linker protonation state, enabling direct interrogation of the role of the coordinating species on crystal growth. Judicious choice of modulator under buffered conditions leads to molecular control over crystal morphology. Together, these studies provide two examples in which molecular approaches to the design of materials enable new fundamental insights into complex solids and surfaces.