The advancement of improved photoactive materials requires a deep understanding of their correlated spatial, spectral, and temporal properties. In principle, correlated time-resolved microscopy techniques are capable of capturing such information. Here, scanning electron microscopy (SEM) correlated to transient absorption microscopy (TAM) is used to study heterogeneities in thin films of 3D perovskites. Statistical analysis of thousands of distinct spatial locations reveals the effects of grain boundaries and crystal size on carrier dynamics. Further, a new class of 2D perovskite materials is discovered by exploiting alloying of the organic cation. Spectroscopic and theoretical studies show that such structural deformation leads to a blue-shifted bandgap, sub-bandgap trap states with wider energetic distribution, and stronger photoluminescence quenching. These results and methods provide new insights for understanding the structure-property relationship in perovskite materials.

Ultrafast hyperspectral imaging of perovskites materials

ACS Fall 2021

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