Functioned fullerene between the perovskite grains visualized by scanning probe microscopy
作者单位：Department of Microelectronic Science and EngineeringNingbo University
会议名称：《第六届新型太阳能电池材料科学与技术学术研讨会》
会议日期：2019年
学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）]
关 键 词：Current hysteresis perovskite solar cells fullerene grain boundary nanoscopic current
摘 要：In perovskite solar cells(PSCs), hybrid perovskite:fullerene phases have been proposed to suppress macroscopic current hysteresis behavior by alleviating ion migration. However, the understanding of how fullerenes exactly alleviate the current hysteresis and what is the influence of fullerenes in such hybrid phases are still unclear from a microscopic viewpoint. Here, the intentional incorporation of fullerene into perovskite has been employed to examine how fullerene exactly reduces the macroscopic current hysteresis. The location and distribution of fullerenes in the hybrid phase were confirmedly visualized by conductive atomic force microscopy and Kelvin probe force microscopy measurements. Fullerenes located at grain boundaries function as the beneficial effect on choking the channels of ion migration and also as the electron traps that compromise the photocarrier extraction. Macroscopic current hysteresis originating from the influxes of all nanoscopic grain boundary current signals is avoided in PSCs based on the hybrid perovskite:fullerene phases. Our results not only provide the strong correlation between nanoscopic and macroscopic current hysteresis behaviors, but also clearly clarify the role of fullerene how to reduce the current hysteresis in hybrid phases and thus prototype devices.