This presentation will describe our efforts in developing single-molecule approaches to study catalysis, focusing on two stories. The first story will be about our work in using redox-selective super-resolution reaction imaging and sub-particle photocurrent measurements to determine the relation between charge-carrier surface activity and water oxidation efficiency on a semiconductor photoanode during photoelectrochemical water oxidation. I will describe how the mapping of hole and electron activity leads to the discovery of optimal sites for oxygen evolution catalysts and a strategy for rationally engineering photoelectrodes with catalysts. The second story will be about our work of using magnetic tweezers to track single polymer growth in real time under living polymerization catalysis conditions. I will describe how the real-time growth dynamics of single polymers reveal the formation and unraveling of conformational entanglements that play key roles in the polymerization kinetics and kinetic dispersion among individual polymers.

Key references:

1. J. B. Sambur, T.-Y. Chen, E. Choudhary, G. Chen, E. J. Nissen, E. M. Thomas, N. Zou, P. Chen* "Sub-particle reaction and photocurrent mapping to optimize catalyst-modified photoanodes" Nature 2016, 530, 77-80.

2.  C. Liu, K. Kubo, E. Wang, K.-S. Han, F. Yang, G. Chen, F. A. Escobedo,* G. W. Coates,* P. Chen* "Single polymer growth dynamics" Science 2017, 358, 352-355.