Tailoring quantum dots to photocatalytic transformations and device applications critically depends on knowing quantum dot redox potentials across a wide range of charge carrier densities. On a fundamental level, their charging and discharging resembles both molecular redox reactivity and electron transfer phenomena of bulk electrodes. Studying charge accumulation in quantum dots therefore bridges a “nanoscale gap” between conceptual models of molecular and material redox properties. Surface chemistry is emerging as a key determinant of quantum dot redox potentials, but is inevitably altered by conventional thin-film voltammetric measurement techniques. We will present potentiometric titration as a contactless method for quantifying quantum dot redox potentials with simultaneous control over charge carrier densities and identity of charge compensating surface ions. In addition, we will demonstrate how a simple and general quantum-classical theoretical model provides insight into the influence of common experimental parameters over quantum dot redox potentials. Together, these powerful measurement and theoretical tools allow investigation of fascinating electron transfer behavior unique to the nanoscale gap.

Measurement and theoretical modelling of multiply charged quantum dot redox potentials

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.