Impact of Capacitive Effect and Ion Migration on the Hysteretic Behavior of Perovskite Solar Cells
Impact of Capacitive Effect and Ion Migration on the Hysteretic Behavior of Perovskite Solar Cells
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DOI：
10.1021/acs.jpclett.5b02229
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发表时间：
2015-12-03
影响因子：
5.7
通讯作者：
Priya, Shashank
中科院分区：
文献类型：
--
作者：
Chen, Bo;Yang, Mengjin;Priya, Shashank
在过去的五年中，基于有机金属卤化物钙钛矿的钙钛矿太阳能电池（PSC）表现出非凡的光伏（PV）性能。然而，PSC的PV测量已被广泛认为取决于电压扫描条件（滞后电流密度电压[J-V]行为）以及电压处理历史。在这项研究中，我们发现不同的PSC反应可归因于两个原因。首先，与电极极化相关联的电容效应提供了修改J-V响应的缓慢瞬态非稳态光电流。第二，由离子迁移引起的界面势垒的修改可以调制电荷收集效率，使得它引起伪稳态光电流，其根据先前的电压调节而改变。这两种现象都受到外界面处离子积累的强烈影响，但它们的电学和PV效应是不同的。电容电流衰减的时间尺度是秒的量级，而移动的离子的缓慢重新分布需要几分钟。
In the past five years, perovskite solar cells (PSCs) based on organometal halide perovskite have exhibited extraordinary photovoltaic (PV) performance. However, the PV measurements of PSCs have been widely recognized to depend on voltage scanning condition (hysteretic current density voltage [J-V] behavior), as well as on voltage treatment history. In this study, we find that varied PSC responses are attributable to two causes. First, capacitive effect associated with electrode polarization provides a slow transient non-steady-state photocurrent that modifies the J-V response. Second, modification of interfacial barriers induced by ion migration can modulate charge-collection efficiency so that it causes a pseudo-steady-state photocurrent, which changes according to previous voltage conditioning. Both phenomena are strongly influenced by ions accumulating at outer interfaces, but their electrical and PV effects are different. The time scale for decay of capacitive current is on the order of seconds, whereas the slow redistribution of mobile ions requires several minutes.