Charge Transfer from Methylammonium Lead Iodide Perovskite to Organic Transport Materials: Efficiencies, Transfer Rates, and Interfacial Recombination

Hutter, Eline M.; Hofman, Jan-Jaap; Petrus, Michiel L.; Mös, Michiel; Abellon, Ruben D.; Docampo, Pablo und Savenije, Tom J. (2017): Charge Transfer from Methylammonium Lead Iodide Perovskite to Organic Transport Materials: Efficiencies, Transfer Rates, and Interfacial Recombination. In: Advanced Energy Materials, Vol. 7, No. 13, 1602349

Abstract

Perovskite-based photovoltaics have been rapidly developed, with record power conversion efficiencies now exceeding 22%. In order to rationally design efficient and stable perovskite solar cells, it is important to understand not only charge trapping and recombination events, but also processes occurring at the perovskite/transport material (TM) interface, such as charge transfer and interfacial recombination. In this work, time-resolved microwave conductivity measurements are performed to investigate these interfacial processes for methylammonium lead iodide and various state-of-the-art organic TMs. A global kinetic model is developed, which accurately describes both the dynamics of excess charges in the perovskite layer and transfer to charge-specific TMs. The authors conclude that for state-of-the-art materials, such as Spiro-OMeTAD and PCBM, the charge extraction efficiency is not significantly affected by intra-band gap traps for trap densities under 10(15) cm(-3). Finally, the transfer rates to C60, PCBM, EDOT-OMeTPA, and Spiro-OMeTAD are sufficient to outcompete second order recombination under excitation densities representative for illumination by AM1.5.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Research Centers: Center for NanoScience (CENS)
• Subjects: 500 Science > 540 Chemistry; 500 Science > 500 Science
• ISSN: 1614-6832
• Language: English