Electron-hole diffusion lengths exceeding 1 micrometer in an organometal trihalide perovskite absorber.

Journal article

Organic-inorganic perovskites have shown promise as high-performance absorbers in solar cells, first as a coating on a mesoporous metal oxide scaffold and more recently as a solid layer in planar heterojunction architectures. Here, we report transient absorption and photoluminescence-quenching measurements to determine the electron-hole diffusion lengths, diffusion constants, and lifetimes in mixed halide (CH3NH3PbI(3-x)Cl(x)) and triiodide (CH3NH3PbI3) perovskite absorbers. We found that the diffusion lengths are greater than 1 micrometer in the mixed halide perovskite, which is an order of magnitude greater than the absorption depth. In contrast, the triiodide absorber has electron-hole diffusion lengths of ~100 nanometers. These results justify the high efficiency of planar heterojunction perovskite solar cells and identify a critical parameter to optimize for future perovskite absorber development.

Authors: Stranks, S; Eperon, G; Grancini, G; Menelaou, C; Alcocer, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for the Advancement of Science
• Journal: Science (New York, N.Y.)
• Volume: 342
• Issue: 6156
• Pages: 341-344
• Publication date: 2013-10-18
• DOI: 10.1126/science.1243982
• EISSN: 1095-9203
• ISSN: 0036-8075
• Language: English