Charge extraction via graded doping of hole transport layers gives highly luminescent and stable metal halide perovskite devices.

ABSTRACT: One source of instability in perovskite solar cells (PSCs) is interfacial defects, particularly those that exist between the perovskite and the hole transport layer (HTL). We demonstrate that thermally evaporated dopant-free tetracene (120 nm) on top of the perovskite layer, capped with a lithium-doped Spiro-OMeTAD layer (200 nm) and top gold electrode, offers an excellent hole-extracting stack with minimal interfacial defect levels. For a perovskite layer interfaced between these graded HTLs and a mesoporous TiO₂ electron-extracting layer, its photoluminescence yield reaches 15% compared to 5% for the perovskite layer interfaced between TiO₂ and Spiro-OMeTAD alone. For PSCs with graded HTL structure, we demonstrate efficiency of up to 21.6% and an extended power outp

SUBMITTER: Abdi-Jalebi M 

PROVIDER: S-EPMC6377269 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature