Research

Single-particle, Single-molecule Photoelectrochemistry

Research Overview

Our research focuses on developing in situ spectroscopic and electrochemical imaging methods to study nanomaterials for applications in solar energy conversion and catalysis. We are interested in determining surface structure/reactivity/energy conversion correlations at the sub-nanoparticle-level and using this knowledge to rationally design functional materials. Our ultimate goal is to understand and exploit nanoparticle-nanoparticle interactions for the design of high-efficiency energy conversion devices.

Why Single-Particle?

Nanomaterial samples are generally heterogeneous. That is, the chemical composition, size, and shape varies both at the inter- and intra-particle levels (see images below). Conventional analytical techniques measure the average behavior of many, individual nanomaterials and therefore cannot resolve single nanoparticle behavior. What if a minor, “magic” population contributes to all of the sample’s function? Our group circumvents ensemble averaging by using sub-particle-level characterization techniques.

Why Single-Molecule Photoelectrochemistry?

Single-molecule methods are widely used in chemical biology to spatially and temporally resolve cellular processes within a complex environment. Our mission is to integrate single-molecule methods into the field of photoelectrochemistry to understand how single nanomaterials behave withinin complex architectures and under working device conditions. Our single-particle, single-molecule approach spatiotemporally resolves the fundamental processes involved in photoelectrochemical energy conversion — we visualize and count charge transfer reactions at the semiconductor-liquid interface. We see exciting opportunities to apply these techniques to address open questions in three energy-related research areas: confined semiconductorsplasmonics, and sensitized solar cells.