Pentadiamond: a highly efficient electron transport layer for perovskite solar cells

• Main Authors: Zhou, Kun, Sun, Ping-Ping, Kripalani, Devesh Raju, Bai, Lichun, Chi, Weijie
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Materials; Charge-Carrier Mobility; High-Performance
• Online Access: https://hdl.handle.net/10356/160165
• Institution: Nanyang Technological University

Rapid improvements in the power conversion efficiency of perovskite solar cells (PSCs), to as high as 25.5%, have aroused great interest in perovskite-based systems. Nevertheless, for achieving highly efficient photovoltaic performance, a persistent challenge lies in carrier extraction at the interface between the perovskite and electron transport layers, which requires that the electron transport material (ETM) should possess high carrier mobility and a small energy level offset with the perovskite. Herein, we find that pentadiamond, a new carbon phase, is a highly efficient ETM that could exhibit desirable photovoltaic performance by enhancing the interface carrier extraction. Based on first-principles calculations, pentadiamond displays a semiconducting nature with an indirect bandgap of 2.46 eV. A favorable band alignment at the pentadiamond/MAPbI3 interface demonstrates a large driving force for the interface electron transfer. Furthermore, the calculated electron mobility of pentadiamond can be as high as 351.72 cm2 s-1 V-1, thus highlighting its outstanding electron transport capability. Interestingly, the calculated transferred charge across the interface between MAPbI3 and pentadiamond reaches 1.29 electrons, indicating the rather high interface transport capacity. Such interesting findings feature pentadiamond as a highly efficient ETM with great prospects and applications in PSCs.