实验分析了在15%、50%和90%RH湿度条件下CH3NH3PbI3薄膜退化过程.通过XRD测量发现不同湿度环境中CH3NH3PbI3薄膜的退化产物为PbI2,且在90%相对湿度(RH)环境下还观测到了退化中间产物水合物(CH3NH3)4PbI6·2H2O.不同湿度环境中CH3NH3PbI3薄膜退化速度不同,湿度越大,退化速度越快.通过载流子动力学的测量发现随着退化时间增长,CH3NH3PbI3薄膜光生载流子数量不断减小.低湿度环境下CH3NH3PbI3薄膜在退化过程中表现出缺陷钝化现象,载流子复合寿命随退化时间呈先上升后下降趋势.而在高湿度条件下,CH3NH3PbI3薄膜出现缺陷增加现象,载流子复合寿命随退化时间呈下降趋势.
The degradation process of CH3NH3PbI3 films under 15%, 50% and 90% relative humidity(RH)was analyzed.The degradation product of CH3NH3PbI3film in different humidity environments was found to be PbI2 according to XRD measurement.The intermediate product was also observed in the 90% RH environment, which is similar like(CH3NH3)4PbI6·2H2O.CH3NH3PbI3 film exhibits a faster degradation rates in high RH environment.During CH3NH3PbI3 film degradation process its photo induced carriers quantity also decreases with aging time.In high RH environment carriers lifetime of CH3NH3PbI3 film reduces monotonously with aging time.While in low RH environment carrier lifetime increases at first stage of degradation process, which means that low RH atmosphere can passivate defects in CH3NH3PbI3 thin film.
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