The Roles of Ion Migration on Perovskite Solar Cell Operational Stability at Various Illumination Intensities
Tanko, K.T., Raga, S.R., Vahedigharehchopogh, N., Baumann, F., Karimipour, M., Miranda-Gamboa, R.A. and Lira-Cantú, M. (2025), Sol. RRL, 9: 2500162. https://doi.org/10.1002/solr.202500162
This academic paper explores the operational stability of perovskite solar cells (PSCs), focusing on how ion migration impacts their degradation. The authors utilise a non-destructive method combining maximum power point (MPP) tracking with electrochemical impedance spectroscopy (EIS) to observe the temporal evolution of degradation mechanisms under various illumination intensities. Their findings indicate that increased ionic density and mobility within the perovskite layer lead to significant losses in performance, especially under lower light conditions relevant for indoor photovoltaics. Ultimately, the study suggests that EIS is a valuable tool for understanding and improving the long-term stability of PSCs.
PAIOS System in Perovskite Solar Cell Research
The researchers used a PAIOS setup from FLUXiM AG for Electrochemical Impedance Spectroscopy (EIS) measurements.
Specifically, here's how PAIOS was utilised:
• EIS Measurements: EIS was performed with a VAC perturbation of 10mV.
• Conditions: During these measurements, the perovskite solar cells (PSCs) were maintained at open-circuit voltage (Voc) and under a continuous N2 gas flow.
• Light Intensity Variation: The white LED light intensity was varied by four orders of magnitude during the EIS measurements.
• Post-MPP Testing: After the maximum power point (MPP) test, the cells were immediately transferred to the PAIOS system, which was kept under an N2 atmosphere. Additional J-V curves were measured before and after the EIS test to confirm that the cells did not experience abnormal degradation during the approximately 1-hour EIS scan.
• J-V Measurement Details (in PAIOS): For J-V curves measured in PAIOS, they were performed under 60mW cm−2 white LED light, with 5 mV steps, a 107 mV/s scan rate, 40ms settling time, and 10ms measurement time per point.
• LED Light Spectrum and Calibration: The spectral irradiance of the LED light in PAIOS was determined using a CSS-45 with a CSS-D spectral light detector (Gigahertz-Optik). Radiometric and photometric calculations were conducted according to international calibration standards (January 2025), with uncertainties of ±6% for spectral irradiance and ±4% for illuminance. The LED light spectrum was practically identical across both low and high irradiance conditions, indicating consistent performance.
How Litos Lite was used
The LITOS Lite setup from FLUXiM AG was used for Maximum Power Point (MPP) tracking stability measurements of perovskite solar cells (PSCs).
Here's how it was utilised:
• Purpose: LITOS Lite facilitated the monitoring of PSC stability under operational conditions, which is crucial for their development. It provided a controlled environment for observing durability and reliability.
• Conditions: Unencapsulated PSC devices were placed in the LITOS Lite setup. These cells were subjected to constant 1 sun illumination using a calibrated WAVELABS LS2 AAA solar simulator (LED). A continuous N2 gas flow was maintained, and the temperature was set at 65°C.
• Measurements: Current and voltage measurements at the MPP were saved every 15 minutes