Stability study in organic solar cells based on PTB7:PC71BM and the scaling effect of the active layer

Autor: Enrique Pérez-Gutiérrez, J. C. Nolasco, José-Luis Maldonado, Denisse Barreiro-Argüelles, Marco-Antonio Meneses-Nava, Daniel Romero-Borja, Gabriel Ramos-Ortiz
Rok vydání: 2018
Předmět:
Zdroj: Solar Energy. 163:510-518
ISSN: 0038-092X
DOI: 10.1016/j.solener.2018.01.090
Popis: Performance and stability of organic photovoltaic cells (OPVs) based on the benchmark bulk heterojunction PTB7:PC71BM and the alloy Field’s metal (FM) as top-electrode deposited by doctor blade technique, are fully studied when the active area is scaled by a factor of 25. Power conversion efficiency (PCE) of small active area (0.09 cm2) devices resulted in 7.4 ± 0.8%, which is within the range of values commonly achieved for devices comprising Al as traditional, costly and nonstable top-electrode. However, PCE decreased 60% for scaled OPVs (2.25 cm2). Studies of stability as a function of the active area were performed in accordance with the ISOS-L1 (laboratory simulation of constant lighting) and ISOS-D1 (shelf storage) protocols for devices tested in air and without encapsulation. The time to reach 50% of the initial PCE (T50) is about 14 h and 2000 h under ISOS-L1 and ISOS-D1 protocols, respectively, with a tendency of stability improvement for scaled devices. A whole PV analysis through the single diode model, impedance spectroscopy, and light beam induced voltage (LBIV) measurements is presented. Our results are a good indication that FM top-electrode, of cheap and easy deposition under vacuum free conditions, provides an acceptable photovoltaic performance after scaling the active area.
Databáze: OpenAIRE