Due to their superior photoluminescence(PL)quantum yield(QY) and tunable optical band gap,all-inorganic CsPbBr_3 perovskite quantum dots(QDs) have attracted intensive attention for the application in solar cells,light...Due to their superior photoluminescence(PL)quantum yield(QY) and tunable optical band gap,all-inorganic CsPbBr_3 perovskite quantum dots(QDs) have attracted intensive attention for the application in solar cells,light emitting diodes(LED),photodetectors and laser devices.In this scenario,the stability of such materials becomes a critical factor to be revealed.We hereby investigated the long-term stability of as-synthesized CsPbBr_3 QDs suspended in toluene at various environmental conditions.We found light illumination would induce drastic photo-degradation of CsPbBr_3 QDs.The steady-state spectroscopy,transmission electron microscopy(TEM),and X-ray diffraction(XRD)verified that CsPbBr_3 QDs tend to aggregate to form larger particles under continuous light soaking.In addition,decreasing PL QY of the QDs during light soaking indicates the formation of trap sites.Our work reveals that the main origin of instability in CsPbBr_3 QDs and provides reference to engineer such QDs towards optimal device application.展开更多
基金supported by the National Priorities Research Program from the Qatar National Research Fund(a member of Qatar Foundation)(NPRP7-227-1-034)the Swedish Foundation for International Cooperation in Research and Higher Education(STINT,CH2015-6232)the Academy of Finland,and the Program of Study Abroad for Young Teachers by Agricultural University of Hebei
文摘Due to their superior photoluminescence(PL)quantum yield(QY) and tunable optical band gap,all-inorganic CsPbBr_3 perovskite quantum dots(QDs) have attracted intensive attention for the application in solar cells,light emitting diodes(LED),photodetectors and laser devices.In this scenario,the stability of such materials becomes a critical factor to be revealed.We hereby investigated the long-term stability of as-synthesized CsPbBr_3 QDs suspended in toluene at various environmental conditions.We found light illumination would induce drastic photo-degradation of CsPbBr_3 QDs.The steady-state spectroscopy,transmission electron microscopy(TEM),and X-ray diffraction(XRD)verified that CsPbBr_3 QDs tend to aggregate to form larger particles under continuous light soaking.In addition,decreasing PL QY of the QDs during light soaking indicates the formation of trap sites.Our work reveals that the main origin of instability in CsPbBr_3 QDs and provides reference to engineer such QDs towards optimal device application.
