Elucidating the charge carrier separation and working mechanism of CH 3 NH 3 PbI 3− x Cl x perovskite solar cells Academic Article uri icon

abstract

  • Abstract Developments in organic–inorganic lead halide-based perovskite solar cells have been meteoric over the last 2 years, with small-area efficiencies surpassing 15%. We address the fundamental issue of how these cells work by applying a scanning electron microscopy-based technique to cell cross-sections. By mapping the variation in efficiency of charge separation and collection in the cross-sections, we show the presence of two prime high efficiency locations, one at/near the absorber/hole-blocking-layer, and the second at/near the absorber/electron-blocking-layer interfaces, with the former more pronounced. This 'twin-peaks' profile is characteristic of ap–i–n solar cell, with a layer of low-doped, high electronic quality semiconductor, between a p-and an n-layer. If the electron blocker is replaced by a gold contact, only a heterojunction at the absorber/hole-blocking interface …

publication date

  • January 1, 2014