am9b03822_si_002.zip (67.24 MB)
Single-Particle Organolead Halide Perovskite Photoluminescence as a Probe for Surface Reaction Kinetics
dataset
posted on 2019-04-22, 00:00 authored by Juvinch
R. Vicente, Ali Rafiei Miandashti, Kurt Waldo E. Sy Piecco, Joseph R. Pyle, Martin E. Kordesch, Jixin ChenPhotoluminescence (PL) of organolead
halide perovskites (OHPs)
is sensitive to OHPs’ surface conditions and is an effective
way to report surface states. Literature has reported that at the
ensemble level, the PL of photoexcited OHP nanorods declines under
an inert nitrogen (N2) atmosphere and recovers under subsequent
exposure to oxygen (O2). At the single-particle level,
we observed that OHP nanorods photoblink at rates dependent on both
the excitation intensity and the O2 concentration. Combining
the two sets of information with the charge-trapping/detrapping mechanism,
we are able to quantitatively evaluate the interaction between a single
surface defect and a single O2 molecule using a new kinetic
model. The model predicts that the photodarkening of OHP nanorods
in the N2 atmosphere has a different mechanism than conventional
PL quenching, which we call photo-knockout. This model provides fundamental
insights into the interactions of molecular O2 with OHP
materials and helps design a suitable OHP interface for a variety
of applications in photovoltaics and optoelectronics.