Efficient and stable large-area perovskite solar cells with inorganic charge extraction layers

TLDR

Perovskite solar cells have seen dramatic PCE gains, yet high efficiencies are usually achieved on sub‑0.1 cm² areas with limited stability. Using heavily doped inorganic charge extraction layers, planar PSCs with 10–20 nm thick layers achieved >15 % PCE on >1 cm² apertures, eliminated hysteresis, and retained >90 % of initial PCE after 1000 h light soaking.

Abstract

The recent dramatic rise in power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) has triggered intense research worldwide. However, high PCE values have often been reached with poor stability at an illuminated area of typically less than 0.1 square centimeter. We used heavily doped inorganic charge extraction layers in planar PSCs to achieve very rapid carrier extraction, even with 10- to 20-nanometer-thick layers, avoiding pinholes and eliminating local structural defects over large areas. The robust inorganic nature of the layers allowed for the fabrication of PSCs with an aperture area >1 square centimeter that have a PCE >15%, as certified by an accredited photovoltaic calibration laboratory. Hysteresis in the current-voltage characteristics was eliminated; the PSCs were stable, with >90% of the initial PCE remaining after 1000 hours of light soaking.