CBE Seminar Series: Yingjie Zhang

The structure of solid-liquid interfaces is critical for a large range of systems, including electrochemical energy conversion and storage, corrosion control, water purification, biological signal transduction, and more. However, our understanding of these interfaces remains highly limited. Existing theory and experimental tools have shed light on the structure of solid surfaces; in contrast, the configuration and distribution of molecular and charged species of interfacial liquids remain elusive. The problem becomes more challenging in realistic systems where the solid surfaces inevitably contain various heterogeneities, such as vacancies, step edges and surface corrugations. In this talk, I will discuss our recent efforts on experimental and theoretical investigations of liquid structure at solid-liquid interfaces. Using in situ 3D atomic force microscopy and surface-sensitive vibrational spectroscopy, we have experimentally determined the structure of a diverse set of solvents and electrolytes near flat and heterogeneous solid surfaces. Furthermore, we have developed a statistical mechanics-based model to both explain the experimental results and predict liquid structures near solid surfaces with arbitrary morphologies. At the end, I will discuss how these results can be revolutionary in surface/interface science and electrochemistry, and how the liquid structures may modulate the electrochemical reaction dynamics.