Unveiling the degraded electron durability in reduced-dimensional perovskites.

The operational stability of reduced-dimensional metal halide perovskites (RD-MHPs) lags far behind the practical requirements for future high-definition displays. Thereinto, the electron durability of RD-MHPs plays a critical role in stable LEDs during continuous operation, however, it still lacks adequate research and a deep understanding. Herein, the electron durability and deterioration mechanism of phenethylammonium (PEA)-modified RD-MHPs are systematically conducted through an photoelectron spectroscopy technique by implementing tunable electron-beam radiation to simulate device operation. The formation of detrimental metallic lead (Pb) caused by the reduction of lead ions (Pb) is observed along with the decomposition of PEA under electron-beam radiation, thereby changing the photophysical properties of PEA-doped RD-MHPs. These results provide deep insight into the process of how injected electrons affect the performance of PEA-doped perovskite LEDs, which may also provide potential guidance for designing robust and effective organic spacers for RD-MHPs.