Collaborative Research: RUI: Instrument Development: Ångström-Scale Operando Spectroscopic Imaging at Heterogeneous Electrochemical Interfaces

Colby College, Waterville ME

Investigators

Abstract

With support from the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry and the Established Program to Stimulate Competitive Research (EPSCoR) Program, Naihao Chiang from the University of Houston and Lindsey Madison from Colby College are studying solution phase heterogeneous electrochemical systems using advances in hyperspectral imaging and simulation tools. Chemical reactions that occur at an electrode surface are composed of a mixture of molecules, which leads to varying atomic scale heterogeneity in composition, electronic structure, and morphology. To better understand these complex systems, Dr. Chiang and his students will construct a custom-built electrochemical tip-enhanced Raman spectroscopy (EC-TERS) instrument to experimentally characterize electrode surfaces while Dr. Madison and her students will provide complementary information to determine and predict molecular structures on the electrode surfaces. Chiang and Madison are also developing after-school outreach activities to engage with students in primary and secondary education. In this collaborative project, synergistic computational and experimental studies of electrochemical reactions at the atomic level will be studied through the development of an electrochemical tip-enhanced Raman spectroscopy (EC-TERS) imaging instrument. Predictions on the effect of small molecule oxidation states on surface binding configurations and their non-resonant Raman response will be made using ab initio molecular dynamics (AIMD) and by time dependent density functional theory (TD-DFT). By improving capabilities in spatial resolution through advances in instrumentation, the interplay between electrical potential, absorbed molecules, and electrolytes at EC interfaces will be studied. Proof-of-concept systems will be explored to guide future applications in advanced electrochemistry applications such as batteries and catalysts. 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.