Department of Chemistry and Center for Nano Science (CeNS), LMU Munich , Butenandtstr. 5-13, 81377 Munich, Germany.
Nanosystems Initiative Munich (NIM), LMU Munich , Schellingstr. 4, 80799 Munich, Germany.
ACS Appl Mater Interfaces. 2017 Nov 1;9(43):37655-37661. doi: 10.1021/acsami.7b09567. Epub 2017 Oct 19.
Understanding the charge transport characteristics and their limiting factors in organolead halide perovskites is of great importance for the development of competitive and economically advantageous photovoltaic systems derived from these materials. In the present work, we examine the charge carrier mobilities in CHNHPbI (MAPI) thin films obtained from a one-step synthesis procedure and in planar n-i-p devices based on these films. By performing time-of-flight measurements, we find mobilities around 6 cm/V s for electrons and holes in MAPI thin films, whereas in working solar cells, the respective effective mobility values are reduced by 3 orders of magnitude. From complementary experiments on devices with varying thicknesses of electron and hole transport layers, we identify the charge extraction layers and the associated interfaces rather than the perovskite material itself as the major limiting factors of the charge carrier transport time in working devices.
了解有机卤化铅钙钛矿中的电荷输运特性及其限制因素对于开发具有竞争力和经济优势的光伏系统非常重要。在本工作中，我们研究了通过一步合成法获得的 CHNHPbI（MAPI）薄膜中的载流子迁移率以及基于这些薄膜的平面 n-i-p 器件中的载流子迁移率。通过飞行时间测量，我们发现 MAPI 薄膜中的电子和空穴迁移率约为 6 cm/V s，而在工作太阳能电池中，相应的有效迁移率值降低了 3 个数量级。通过对具有不同电子和空穴传输层厚度的器件进行补充实验，我们确定了电荷提取层和相关界面，而不是钙钛矿材料本身，是工作器件中电荷载流子输运时间的主要限制因素。
