| 초록 |
Lead halide perovskite (LHP) has drawn attention in the optoelectronic field because of its bandgap tunability, strong luminescence and a narrow emission wavelength width. However, the application of LHP is still limited because of poor stability, especially in the presence of water. In this work, we report a simple strategy of passivating perovskite with lead sulfate layer by introducing sulfuric acid solution. The synthesized lead halide perovskite, MAPbBr3, reacted with sulfate ion and the perovskite surfaces were passivated with lead sulfate. The bright green-emitting perovskite maintained its luminescence in the liquid water for weeks because water-insoluble lead sulfate strongly bound to the perovskite surfaces by chemical bonds. The passivated LHPs were characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD) and photoluminescence (PL) spectroscopy. The photoluminescence quantum yield of passivated LHPs was remarkably increased from 2.6% to 80% with narrow full width at half maximum of about 20 nm. |
