presenter：jiazhuo nie (espci paris/sorbonne university)
topic：in-situ interfacial temperature evolution of perovskite solar cells over degradation measurement achieved by up-conversion nanoparticles
time：10:30 am, oct 18th (friday)
location：909-b
abstract:：
the instability of pscs remains a significant challenge, as they tend to degrade upon exposure to environmental factors, such as ultraviolet (uv) radiation, oxygen, humidity, and temperature. the origins have been linked to halide segregation, ion migration, and decomposition. in previous studies, various environmental factors have been often treated as independent variables while the evolution of the solar cells' pce was monitored so that different engineering approaches can be identified to mitigate the undesirable instability of pscs. however, during psc degradation, apart from the macroscopic device performance, other properties of the different layers involved and their interfaces also undergo continuous changes, such as material composition and their optical properties (e.g. absorption and photoluminescence (pl)), leading to changes in the electrical properties and thermal environment of the device.
in this work, we introduce a novel local electro-optical scanning technique to monitor in-situ temperature fluctuations, photoluminescence (pl) intensity, and changes in power conversion efficiency (pce) of two distinct compositions of pscs (fa0.9ma0.1pbi3 & fa0.87ma0.13pbi2.87br0.13) at the nanoscale during degradation. this method leverages inorganic er3 doped nayf4 colloidal nanoparticles. to the best of our knowledge, this is the first instance where the correlation between nanoscale temperature elevation inside solar cells and degradation has been experimentally unveiled.
biography：
jiazhuo nie is a 3rd year phd student at espci paris-psl university focus on the degradation of perovskite solar cells. he obtained master and bachelor degree at the xi’an jiaotong university on energy and thermal engineering during 2015 to 2022. then he joined espci as a phd student in 2022.
contact：prof. sun baoquan