Collaborative Research: Coupling between Interfacial Electrostatics and Surface Structures at Transition-Metal Oxide/Liquid Interfaces

NON-TECHNICAL ABSTRACT When a solid touches a liquid such as water, the surface can change its structure in response to the fluid’s electrical properties. Understanding how and why these changes occur is a major scientific challenge and crucial for a wide range of technologies, including next-generation microelectronics, corrosion-protective coatings, and chemical processing and water remediation systems. This collaborative project, with support from the Solid State and Materials Chemistry program in NSF’s Materials Research Section A and the Electrochemical Systems program in NSF’s Chemical, Bioengineering, Environmental and Transport Systems Section A, aims to uncover how electrical charges and liquids alter the surface structures at the atomic level. By combining precise atomic-level material manufacturing, in-liquid imaging techniques, and powerful computer simulations, the team will observe how water and ions such as protons influence surfaces and the structure and properties of metal oxide surfaces. The fundamental knowledge generated by this research enables the design of more durable and efficient materials for use in complex liquid environments. Furthermore, this project provides highly interdisciplinary training for students across three universities to gain valuable, cross-cutting expertise in materials synthesis, advanced characterization, and computational modeling. TECHNICAL ABSTRACT This project, supported by the Solid State and Materials Chemistry program in NSF’s Materials Research Section A and the Electrochemical Systems program in NSF’s Chemical, Bioengineering, Environmental and Transport Systems Section A, aims to decipher the coupling between water-solid interfacial electrostatics and structure. Focusing on 3d-transition-metal-oxide systems such as Co-based perovskites, the principal investigators at the University of Nebraska-Lincoln and Cornell University investigate how electrochemical potentials and solvation layers dictate surface atomic arrangements. The methodology integrates density functional theory calculations to model the electric field and solvation at the interface, while leveraging molecular beam epitaxy for thin-film synthesis. Experimental validation employs second harmonic generation and atomic force microscopy to characterize surface structure and morphology in liquids. The expected outcome is a comprehensive framework to explain how polar oxide surfaces restructure to evade the polar catastrophe in liquid media, and how applied potentials drive structural rearrangements within the electrical double layer. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.