Fig. 5
Correlation between photocurrent and ferroic domains of CH3NH3PbI3 crystal across phase transition. a PFM mapping. b Photocurrent distribution under no DC bias following ferroic domain pattern in a with reduced photocurrent in polar domains. c Surface potential distribution under light follows ferroic domain pattern in Fig. 3a–d with negatively shifted potential in polar domains; and d photocurrent distribution in a separate domain pattern at different temperatures across phase transition, showing the disappearing domain pattern at 70 °C upon heating and its re-emergence at 35 °C after cooling
