TY - JOUR
T1 - Energetics and Energy Loss in 2D Ruddlesden–Popper Perovskite Solar Cells
AU - Yang, Jianming
AU - Xiong, Shaobing
AU - Song, Jingnan
AU - Wu, Hongbo
AU - Zeng, Yihan
AU - Lu, Linyang
AU - Shen, Kongchao
AU - Hao, Tianyu
AU - Ma, Zaifei
AU - Liu, Feng
AU - Duan, Chungang
AU - Fahlman, Mats
AU - Bao, Qinye
N1 - Publisher Copyright:
© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2020/6/1
Y1 - 2020/6/1
N2 - 2D Ruddlesden–Popper perovskites (RPPs) are emerging as potential challengers to their 3D counterpart due to superior stability and competitive efficiency. However, the fundamental questions on energetics of the 2D RPPs are not well understood. Here, the energetics at (PEA)2(MA)n−1PbnI3n+1/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) interfaces with varying n values of 1, 3, 5, 40, and ∞ are systematically investigated. It is found that n–n junctions form at the 2D RPP interfaces (n = 3, 5, and 40), instead of p–n junctions in the pure 2D and 3D scenarios (n = 1 and ∞). The potential gradient across phenethylammonium iodide ligands that significantly decreases surface work function, promotes separation of the photogenerated charge carriers with electron transferring from perovskite crystal to ligand at the interface, reducing charge recombination, which contributes to the smallest energy loss and the highest open-circuit voltage (Voc) in the perovskite solar cells (PSCs) based on the 2D RPP (n = 5)/PCBM. The mechanism is further verified by inserting a thin 2D RPP capping layer between pure 3D perovskite and PCBM in PSCs, causing the Voc to evidently increase by 94 mV. Capacitance–voltage measurements with Mott–Schottky analysis demonstrate that such Voc improvement is attributed to the enhanced potential at the interface.
AB - 2D Ruddlesden–Popper perovskites (RPPs) are emerging as potential challengers to their 3D counterpart due to superior stability and competitive efficiency. However, the fundamental questions on energetics of the 2D RPPs are not well understood. Here, the energetics at (PEA)2(MA)n−1PbnI3n+1/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) interfaces with varying n values of 1, 3, 5, 40, and ∞ are systematically investigated. It is found that n–n junctions form at the 2D RPP interfaces (n = 3, 5, and 40), instead of p–n junctions in the pure 2D and 3D scenarios (n = 1 and ∞). The potential gradient across phenethylammonium iodide ligands that significantly decreases surface work function, promotes separation of the photogenerated charge carriers with electron transferring from perovskite crystal to ligand at the interface, reducing charge recombination, which contributes to the smallest energy loss and the highest open-circuit voltage (Voc) in the perovskite solar cells (PSCs) based on the 2D RPP (n = 5)/PCBM. The mechanism is further verified by inserting a thin 2D RPP capping layer between pure 3D perovskite and PCBM in PSCs, causing the Voc to evidently increase by 94 mV. Capacitance–voltage measurements with Mott–Schottky analysis demonstrate that such Voc improvement is attributed to the enhanced potential at the interface.
KW - 2D Ruddlesden–Popper perovskites
KW - energetics
KW - energy loss
KW - open-circuit voltage
KW - perovskite solar cells
UR - https://www.scopus.com/pages/publications/85084457742
U2 - 10.1002/aenm.202000687
DO - 10.1002/aenm.202000687
M3 - 文章
AN - SCOPUS:85084457742
SN - 1614-6832
VL - 10
JO - Advanced Energy Materials
JF - Advanced Energy Materials
IS - 23
M1 - 2000687
ER -
