A Novel Anthracene Derivative Used as Cathode Interlayer for Efficient Inverted Perovskite Solar Cell

Abstract

Metal halide hybrid perovskite solar cells have recently emerged as a highly cost‐effective photovoltaic technology. The cathode interlayer plays a critical role in aligning energy levels and promoting charge extraction in inverted perovskite solar cells. Herein, a novel multinitrogen derivative interlayer, Anth‐hpp2, is designed and synthesized consisting of 1,1'‐(4‐(9,10‐di(naphthalen‐2‐yl)anthracen‐2‐yl)pyridine‐2,6‐diyl)bis(1,3,4,6,7,8‐hexahydro‐2H‐pyrimido[1,2‐a] pyrimidine), between the PCBM and top Ag electrode. The superbase group in Anth‐hpp2 effectively contacts the silver electrode, reducing the work function of Ag. Consequently, the power conversion efficiency of the Anth‐hpp2‐based device improved from 16.05% to 20.37%, along with enhancements in short‐circuit current and fill factor. The stabilities of perovskite solar cells are measured with Anth‐hpp2 under N2 storage, and the device efficiency with Anth‐hpp2 decayed by only 5% after fabrication for approximately 2500 h, which is five times that of the control device. This study provides original insights into designing new cathode interlayer materials.