Electron-hole diffusion lengths > 175 μm in solution-grown CH 3 NH 3 PbI 3 single crystals

Balanced carrier diffusion in perovskites The efficient operation of solar cells based on inorganic-organic perovskites requires balanced transport of positive and negative charge carriers over long distances. Dong et al. used a top-seeded solution growth method to obtain millimeter-scale single crystals of the organolead trihalide perovskite CH 3 NH 3 PbI 3 . Under low light illumination, the electron and hole diffusion lengths exceeded 3 mm, and under full sunlight illumination, they exceeded 175 µm. Science , this issue p. 967