posted on 2021-10-12, 21:43authored byNada Mrkyvkova, Vladimír Held, Peter Nádaždy, Riyas Subair, Eva Majkova, Matej Jergel, Aleš Vlk, Martin Ledinsky, Mário Kotlár, Jianjun Tian, Peter Siffalovic
Lead-halide
perovskites have established a firm foothold in photovoltaics
and optoelectronics due to their steadily increasing power conversion
efficiencies approaching conventional inorganic single-crystal semiconductors.
However, further performance improvement requires reducing defect-assisted,
nonradiative recombination of charge carriers in the perovskite layers.
A deeper understanding of perovskite formation and associated process
control is a prerequisite for effective defect reduction. In this
study, we analyze the crystallization kinetics of the lead-halide
perovskite MAPbI3–xClx during thermal annealing, employing in situ photoluminescence (PL) spectroscopy complemented by lab-based grazing-incidence
wide-angle X-ray scattering (GIWAXS). In situ GIWAXS
measurements are used to quantify the transition from a crystalline
precursor to the perovskite structure. We show that the nonmonotonous
character of PL intensity development reflects the perovskite phase
volume, as well as the occurrence of the defects states at the perovskite
layer surface and grain boundaries. The combined characterization
approach enables easy determination of defect kinetics during perovskite
formation in real-time.