Symposium ES15: Fundamental Understanding of the Multifaceted Optoelectronic Properties of Halide Perovskites
James Sadighian, University of Oregon
In Situ Transient Absorption Spectroscopy of Perovskite Nanocrystal Formation and Growth
Written by Gargi Joshi
Perovskite nanocrystals (NC) have attracted significant interest due to their tunable properties and applicability in light-emitting diodes, lasers, and optical sensors. Usually it is difficult to use time-resolved spectroscopy techniques with the fast synthesis rate of preparation of NCs as well as the unstable nucleation centers behaving as nascent nanocrystals. In order to modulate the functional electronic properties of these particles it is of utmost importance to be able to clarify development of the excited stable dynamics during their formation. James Sadighian prepared methylammonium lead halide perovskite NCs by a ligand-mediated NC synthesis comprising of reaction timescales favorable for study via transient absorption spectroscopy. With this room temperature synthesis initiated by solvation of the precursors with passivating ligands, Sadighian has done first known characterization of immature perovskite NCs in the dynamic unstable state. Future work includes measurement of the growth of these NCs in real-time using the single-shot transient absorption spectrometer, which can give entire transient results in a few seconds.