Spin Transport Layer Enhanced Catalytic Reactions

With support of the Chemical Catalysis program in the Division of Chemistry, Professor David Waldeck of the University of Pittsburgh is studying how the spin of electrons affects electrochemical reactions. Although chemists have long known that both the electron spin and charge are important for making and breaking chemical bonds, considerations of the electron charge has dominated past studies in electrochemistry.

Recent work on water splitting, as well as a few other reactions, show that the electron spin can significantly impact reaction selectivity and reaction efficiency. Waldeck will develop new methods to deliver spin-filtered electron currents to conventional achiral catalysts and will use them to study how the electron spin affects electrocatalytic reactions.

Success of this research program promises to introduce a new tool for examining electrochemical reaction mechanisms and for improving the selectivity of electrochemical reactions. The fundamental scientific outcomes of this project have potential impact beyond electrochemical water splitting, with relevance to other processes involving spin transport and new mechanistic views of catalytic reactions.

The graduate, undergraduate, and high school students involved in the project will be trained in unique aspects of electrochemistry and engage in a consortium of research groups involved in chiral induced spin selectivity (CISS) research.

With support of the Chemical Catalysis program in the Division of Chemistry, Professor David Waldeck of the University of Pittsburgh will leverage the chiral induced spin selectivity (CISS) effect, which states that the transmission of electrons through a chiral material depends on their spin, to create spin-filtered electron currents for electrochemistry studies. Waldeck’s team will create heterostructured catalyst scaffolds, which possess an intermediate chiral ‘spin transport layer’, to control the population of electron spins at the catalyst surface.

In this way, they will examine how the electron spin affects multi-electron redox reactions and enantioselective oxidation reactions. For multielectron reactions, they will examine whether (and how) the orientation of the electron spins with respect to each other affects the distribution of chemical products. In enantioselective chemical reactions – a type of reaction that produces chiral molecules with a particular handedness – they will study how the electron spin can be used to spin-polarize the electron clouds of chemical intermediates and direct the chemical reaction toward one ‘molecular handedness’ over the other.

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.