Charge-Carrier Dynamics and Mobilities in Formamidinium Lead Mixed-Halide Perovskites

Waqaas Rehman; Rebecca L Milot; Giles E Eperon; Christian Wehrenfennig; Jessica L Boland; Henry J Snaith; Michael B Johnston; Laura M Herz

doi:10.1002/adma.201502969

Charge-Carrier Dynamics and Mobilities in Formamidinium Lead Mixed-Halide Perovskites

Adv Mater. 2015 Dec 22;27(48):7938-44. doi: 10.1002/adma.201502969. Epub 2015 Sep 24.

Authors

Waqaas Rehman¹, Rebecca L Milot¹, Giles E Eperon¹, Christian Wehrenfennig¹, Jessica L Boland¹, Henry J Snaith¹, Michael B Johnston¹, Laura M Herz¹

Affiliation

¹ Clarendon Laboratory, Oxford University, Parks Road, OX1 3PU, Oxford, UK.

PMID: 26402226
DOI: 10.1002/adma.201502969

Abstract

The mixed-halide perovskite FAPb(Bry I1-y )3 is attractive for color-tunable and tandem solar cells. Bimolecular and Auger charge-carrier recombination rate constants strongly correlate with the Br content, y, suggesting a link with electronic structure. FAPbBr3 and FAPbI3 exhibit charge-carrier mobilities of 14 and 27 cm(2) V(-1) s(-1) and diffusion lengths exceeding 1 μm, while mobilities across the mixed Br/I system depend on crystalline phase disorder.

Keywords: charge diffusion length; charge-carrier recombination; perovskite solar cells; phase disorder; photovoltaics.