Correlated Electrochemical and Optical Imaging of Physical and Catalytic Activities of Single Plasmonic Nanorods

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Pan's group at the University of Alabama - Tuscaloosa is developing technology for rapid analysis and imaging of microscopic motions and interactions of nanomaterials in electrochemical systems. The approach seeks ultrasensitive chemical imaging of particles and their interactions with light to spur chemical transformations. Students working on this interdisciplinary project are trained in both electrochemistry and material science. Educational and outreach activities target recruiting and retention of Alabama students underrepresented in STEM. The project also features community engagement featuring science activities including chemistry demonstration and training modules prepared and disseminated in partnership with Tuscaloosa middle school science teachers. Mechanistic studies show that electrocatalytic activities of electrode materials formed from nanoparticles are highly dependent on structural heterogeneities, electronic and geometric factors, and particle shapes. Catalytic properties of these nanostructured electrode materials are often studied using bulk films. The nature of catalytic reactivity dependence can be obscured during such conventional ensemble-averaging measurements. The Pan lab is working to advance our understanding of these structure-dependent details by developing quantitative analysis methods to reveal the roles of single catalytic nanoparticles in electro- and photocatalytic reactions. Their approach fully integrates light-scattering imaging with microelectrodes to quantify local electro(photo)catalytic activities enabled by plasmonic nanorods while rapidly resolving translational and rotational diffusion, nanorod-enabled chemical transformations, and collision dynamics. The kinetics of catalyzed redox reactions by single nanorods and photoelectrochemical reactions are being investigated to provide insights into single nanorod-mediated (photo)electrochemical activities. 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.