TY - JOUR
T1 - Deciphering the Role of Hole Transport Layer HOMO Level on the Open Circuit Voltage of Perovskite Solar Cells
AU - Jiang, Zhongyao
AU - Du, Tian
AU - Lin, Chieh Ting
AU - Macdonald, Thomas J.
AU - Chen, Jiongye
AU - Chin, Yi Chun
AU - Xu, Weidong
AU - Ding, Bowen
AU - Kim, Ji Seon
AU - Durrant, James R.
AU - Heeney, Martin
AU - McLachlan, Martyn A.
N1 - Generated from Scopus record by KAUST IRTS on 2023-02-14
PY - 2022/1/1
Y1 - 2022/1/1
N2 - With the rapid development of perovskite solar cells, reducing losses in open-circuit voltage (Voc) is a key issue in efforts to further improve device performance. Here it is focused on investigating the correlation between the highest occupied molecular orbital (HOMO) of device hole transport layers (HTLs) and device Voc. To achieve this, structurally similar HTL materials with comparable optical band gaps and doping levels, but distinctly different HOMO levels are employed. Using light-intensity dependent Voc and photoluminescence measurements significant differences in the behavior of devices employing the two HTLs are highlighted. Light-induced increase of quasi-Fermi level splitting (ΔEF) in the perovskite layer results in interfacial quasi-Fermi level bending required to align with the HOMO level of the HTL, resulting in the Voc measured at the contacts being smaller than the ΔEF in the perovskite. It is concluded that minimizing the energetic offset between HTLs and the perovskite active layer is of great importance to reduce non-radiative recombination losses in perovskite solar cells with high Voc values that approach the radiative limit.
AB - With the rapid development of perovskite solar cells, reducing losses in open-circuit voltage (Voc) is a key issue in efforts to further improve device performance. Here it is focused on investigating the correlation between the highest occupied molecular orbital (HOMO) of device hole transport layers (HTLs) and device Voc. To achieve this, structurally similar HTL materials with comparable optical band gaps and doping levels, but distinctly different HOMO levels are employed. Using light-intensity dependent Voc and photoluminescence measurements significant differences in the behavior of devices employing the two HTLs are highlighted. Light-induced increase of quasi-Fermi level splitting (ΔEF) in the perovskite layer results in interfacial quasi-Fermi level bending required to align with the HOMO level of the HTL, resulting in the Voc measured at the contacts being smaller than the ΔEF in the perovskite. It is concluded that minimizing the energetic offset between HTLs and the perovskite active layer is of great importance to reduce non-radiative recombination losses in perovskite solar cells with high Voc values that approach the radiative limit.
UR - https://onlinelibrary.wiley.com/doi/10.1002/admi.202201737
UR - http://www.scopus.com/inward/record.url?scp=85143393853&partnerID=8YFLogxK
U2 - 10.1002/admi.202201737
DO - 10.1002/admi.202201737
M3 - Article
SN - 2196-7350
JO - Advanced Materials Interfaces
JF - Advanced Materials Interfaces
ER -