Dresden 2017 – wissenschaftliches Programm
CPP 8.8: Vortrag
Montag, 20. März 2017, 17:45–18:00, ZEU 222
Double-layer charge selective contacts in perovskite solar cells as a key to improved efficiency and reduced hysteresis effects — •Lukas Kegelmann1, Christian Wolff3, Celline Awino Omondi1, Lars Korte1, Thomas Dittrich1, Dieter Neher3, Bernd Rech1, and Steve Albrecht2 — 1Helmholtz-Zentrum Berlin, Inst. for Silicon Photovoltaics, Berlin, 12489, Germany. — 2Helmholtz-Zentrum Berlin, Young Investigator Group Perovskite Tandem Solar Cells, Berlin, 12489, Germany. — 3University of Potsdam, Soft Matter Physics, Potsdam, 14476, Germany.
Planar low-temperature processed perovskite solar cells without a mesoscopic scaffold are advantageous for a possible large-scale production but often suffer from photocurrent hysteresis, especially in the regular 'n-i-p'-structure. Here, we systematically study the influence of different low-temperature deposited electron transport materials (ETM) on planar regular solar cell characteristics. We further show that an elaborately chosen metal oxide interlayer in an ITO/metal oxide/PCBM double-layer ETM can significantly improve the device performance. J-V measurements reveal substantial reductions of hysteresis effects and enhanced power conversion efficiencies up to a champion stabilized value of 18.0 % for TiO2 interlayers. Surface photovoltage spectroscopy is used to show comparable absorber qualities on all ETMs for the fabrication process used here. Additionally, improved hole blocking for the double-layer structure is suggested by UPS and the metal oxide interlayer is considered to reduce shunt paths as it hampers direct contact between perovskite and the ITO electrode.