采用光谱测量技术分析了CH3NH3PbI3薄膜的光致发光增强效应及其对载流子复合动力学的影响.实验结果表明,增加光浴功率密度有助于提高薄膜的光致发光增强速率,O2环境有利于薄膜的光致发光增强.CH3NH3PbI3薄膜光浴处理引入的光致发光增强效应源于薄膜内缺陷态浓度降低.同时利用微波吸收介电谱技术,表征了CH3NH3PbI3薄膜光浴前后,自由载流子和浅能级束缚载流子的复合动力学.发现光浴后,薄膜的自由载流子和浅能级束缚载流子浓度明显提高.
The photoluminescence enhancement of CH3NH3PbI3 film and its effect on carrier recombination dynamics were studied by using photoluminescence spectroscopy.Experimental results demonstrate that the rate of photoluminescence enhancement is higher when the power density of light soaking increases.And oxygen atmosphere is helpful to photoluminescence enhancement of CH3NH3PbI3 film.The reduction of defect density in the film is the main mechanism responsible for the photoluminescence enhancement.Furthermore,the effect of light soaking on the recombination dynamics of free carriers and shallow trapped carriers was analyzed by microwave absorption dielectric spectroscopy. Densities of free carriers and shallow trapped carriers in CH3NH3PbI3 film show an obvious increase after the light soaking.
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