Unanticipated Interfacial Redox Reaction in the NiO_x Transport Layer of Perovskite Light-Emitting Diodes.

ABSTRACT: This study reveals an unanticipated interfacial redox reaction between the nickel oxide (NiO_x) hole transport layer and perovskite active layer in organolead halide perovskite light-emitting diodes (PeLEDs). Specifically, metallic nickel (Ni⁰) present in the NiO_x layer undergoes oxidation while lead ions (Pb²⁺) from the perovskite precursor are reduced, forming nickel (II) ions (Ni²⁺) and metallic lead (Pb⁰), as confirmed by X-ray photoelectron spectroscopy (XPS). The formation of Pb⁰, a well-known luminescence quenching center, is correlated with the significantly suppressed photoluminescence (PL) before biasing and the pronounced electroluminescence (EL) overshoot observed at the onset of electrical excitation.

SUBMITTER: Do TH 

PROVIDER: S-EPMC12904025 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature