@article{Leguy:2015:10.1038/ncomms8124, author = {Leguy, AMA and Frost, JM and McMahon, AP and Sakai, VG and Kochelmann, W and Law, C and Li, X and Foglia, F and Walsh, A and O'Regan, BC and Nelson, J and Cabral, JT and Barnes, PRF}, doi = {10.1038/ncomms8124}, journal = {Nature Communications}, title = {The dynamics of methylammonium ions in hybrid organic-inorganic perovskite solar cells}, url = {http://dx.doi.org/10.1038/ncomms8124}, volume = {6}, year = {2015} }
TY - JOUR AB - Methylammonium lead iodide perovskite can make high-efficiency solar cells, which also show an unexplained photocurrent hysteresis dependent on the device-poling history. Here we report quasielastic neutron scattering measurements showing that dipolar CH3NH3+ ions reorientate between the faces, corners or edges of the pseudo-cubic lattice cages in CH3NH3PbI3 crystals with a room temperature residence time of ~14 ps. Free rotation, π-flips and ionic diffusion are ruled out within a 1–200-ps time window. Monte Carlo simulations of interacting CH3NH3+ dipoles realigning within a 3D lattice suggest that the scattering measurements may be explained by the stabilization of CH3NH3+ in either antiferroelectric or ferroelectric domains. Collective realignment of CH3NH3+ to screen a device’s built-in potential could reduce photovoltaic performance. However, we estimate the timescale for a domain wall to traverse a typical device to be ~0.1–1 ms, faster than most observed hysteresis. AU - Leguy,AMA AU - Frost,JM AU - McMahon,AP AU - Sakai,VG AU - Kochelmann,W AU - Law,C AU - Li,X AU - Foglia,F AU - Walsh,A AU - O'Regan,BC AU - Nelson,J AU - Cabral,JT AU - Barnes,PRF DO - 10.1038/ncomms8124 PY - 2015/// SN - 2041-1723 TI - The dynamics of methylammonium ions in hybrid organic-inorganic perovskite solar cells T2 - Nature Communications UR - http://dx.doi.org/10.1038/ncomms8124 UR - http://hdl.handle.net/10044/1/25669 VL - 6 ER -
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