Dr. Prashant V. Kamat
University of Notre Dame
Perovskite Photocatalysis. Tracking Electron Transfer at CsPbBr3 Nanocrystal Interface
The rise of metal halide perovskite based solar cell with efficiencies exceeding 25% has rejuvenated interest in nanoscale perovskite materials for photocatalysis. The metal halide perovskites are analogous to metal chalcogenides in the sense that they absorb in the visible region, their bandgap can be tuned through anion composition and size and shape can be readily varied using hot injection synthetic approach. However, relatively few mechanistic studies exist on the photocatalytic reduction and oxidation processes. The softness of perovskite materials makes them susceptible to surface transformation or degradation in polar solvents. Capping with CdS shell allowed us to carry out electron transfer reactions in polar medium. Using viologen as a probe we have now succeeded in probing the electron transfer of CsPbBr3 nanocrystals. The nature of binding of viologen molecule with the surface has direct influence on the charge separation. Ways to stabilize electron transfer product and improve the photocatalytic performance of perovskite nanocrystals will be discussed.
CsPbBr3–CdS Heterostructure: Stabilizing Perovskite Nanocrystals for Photocatalysis. A. Kipkorir, J. Cho, J. T. DuBose and P. V. Kamat, Chem. Sci. 2021, 12, accepted.
Perovskite Photocatalysis. Methyl Viologen Induces Unusually Long-Lived Charge Carrier Separation in CsPbBr3 Nanocrystals S. M. Kobosko, J. T. DuBose and P. V. Kamat ACS Energy Lett. 2020, 5, 1, 221–223.
Probing Perovskite Photocatalysis. Interfacial Electron Transfer between CsPbBr3 and Ferrocene Redox Couple J. T. DuBose and P. V. Kamat J. Phys. Chem. Lett. 2019, 10, 20, 6074-6080
Surface Chemistry Matters. How Ligands Influence Excited State Interactions between CsPbBr3 and Methyl Viologen, J.T. DuBose and P. V. Kamat J. Phys. Chem. C 2020, 124, 24, 12990–12998