Ion migration in a three-dimensional (3D) perovskite is the source of many unique phenomena such as photocurrent hysteresis and a giant switchable photovoltaic effect and can also accelerate the degradation of perovskite-based electronic devices. Here we report the observation of suppressed ion migration along the in-plane direction of layered perovskites by studying the conductivity of layered single-crystal perovskites at varied temperatures. Large-area layered perovskite thin single crystals are synthesized by the space-confined method. The absence of ion migration in these layered perovskites can be explained by an increase in the energy required to form an ion vacancy, compared to 3D perovskites. The suppressed ion migration in layered perovskites indicates that they have intrinsically better stability under an electric field and may contribute to the improved perovskite stability in devices made of layered perovskite through the reduction of ion diffusion-induced perovskite degradation or corrosion of charge transport layers and electrodes.

中文翻译：

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分层钙钛矿中沿平面方向的离子迁移受到抑制

三维（3D）钙钛矿中的离子迁移是许多独特现象（例如光电流滞后和巨大的可切换光伏效应）的来源，并且还可以加速基于钙钛矿的电子设备的退化。在这里，我们通过研究在不同温度下层状单晶钙钛矿的电导率，观察到了抑制的离子沿层状钙钛矿的面内方向迁移的观察。通过空间限制法合成了大面积层状钙钛矿薄单晶。与3D钙钛矿相比，这些层状钙钛矿中没有离子迁移可以解释为形成离子空位所需的能量增加。