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arXiv · 1405.5810

Molecular ferroelectric contributions to anomalous hysteresis in hybrid perovskite solar cells

Jarvist M. Frost·Keith T. Butler·Aron Walsh
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Abstract

We report a model describing the molecular orientation disorder in CH3NH3PbI3, solving a classical Hamiltonian parametrised with electronic structure calculations, with the nature of the motions informed by ab-initio molecular dynamics. We investigate the temperature and static electric field dependence of the equilibrium ferroelectric (molecular) domain structure and resulting polarisability. A rich domain structure of twinned molecular dipoles is observed, strongly varying as a function of temperature and applied electric field. We propose that the internal electrical fields associated with microscopic polarisation domains contribute to hysteretic anomalies in the current--voltage response of hybrid organic-inorganic perovskite solar cells due to variations in electron-hole recombination in the bulk.

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Jarvist M. Frost, Keith T. Butler, Aron Walsh. 2014-06-19. Molecular ferroelectric contributions to anomalous hysteresis in hybrid perovskite solar cells. https://doi.org/10.1063/1.4890246

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