Passivation of oxygen and light induced degradation by the PCBM electron transport layer in planar perovskite solar cells
Autor: | Jinhyun Kim, Chieh-Ting Lin, Shengda Xu, James R. Durrant, Daniel Bryant, Xiaoe Li, Tian Du, Martyn A. McLachlan, Sebastian Pont |
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Přispěvatelé: | EPSRC |
Rok vydání: | 2018 |
Předmět: |
Technology
Materials science Fullerene EFFICIENCY Passivation Energy & Fuels Kinetics Materials Science Energy Engineering and Power Technology chemistry.chemical_element Materials Science Multidisciplinary 02 engineering and technology 010402 general chemistry FILMS 01 natural sciences Oxygen Ion HOMO/LUMO HYSTERESIS Science & Technology STABILITY Renewable Energy Sustainability and the Environment Chemistry Physical PERFORMANCE 021001 nanoscience & nanotechnology Acceptor DIFFUSION 0104 chemical sciences Chemistry Fuel Technology chemistry Chemical engineering Physical Sciences 0210 nano-technology Mesoporous material BEHAVIOR |
Popis: | Herein, we investigate the causes of a 20 fold improved stability of inverted, planar structure devices (ITO/PTAA/CH3NH3PbI3/PCBM/BCP/Cu) compared to conventional structure devices (FTO/compact-TiO2/meso-TiO2/CH3NH3PbI3/spiro-OMeTAD/Au) under oxygen and light stress. The PCBM layer is shown to function as an oxygen diffusion barrier and passivation layer against superoxide mediated degradation. The passivation properties of the PCBM layer are shown to depend on the electron affinity of the fullerene acceptor, attributed to the low LUMO level of PCBM energetically inhibiting superoxide generation. We also find that planar structure devices show slower lateral oxygen diffusion rates than mesoporous scaffold devices, with these slower diffusion rates (days per 100 μm) also being a key factor in enhancing stability. Faster degradation is observed under voltage cycling, attributed to oxygen diffusion kinetics being ion motion dependent. We conclude by discussing the implications of these results for the design of perovskite solar cells with improved resistance to oxygen and light induced degradation. |
Databáze: | OpenAIRE |
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