TY - JOUR
T1 - Direct Measurements of Interfacial Photovoltage and Band Alignment in Perovskite Solar Cells Using Hard X-ray Photoelectron Spectroscopy
AU - Svanström, Sebastian
AU - García Fernández, Alberto
AU - Sloboda, Tamara
AU - Jacobsson, T. Jesper
AU - Zhang, Fuguo
AU - Johansson, Fredrik O.L.
AU - Kühn, Danilo
AU - Céolin, Denis
AU - Rueff, Jean Pascal
AU - Sun, Licheng
AU - Aitola, Kerttu
AU - Rensmo, Håkan
AU - Cappel, Ute B.
N1 - Funding Information:
The authors acknowledge SOLEIL for the provision of synchrotron radiation (proposal numbers: 20161265, 20171063, 20180483, 20181721, and 20191506) facilities at the GALAXIES beamline. Some measurements were carried out at the CoESCA endstation at the BESSY-II electron storage ring operated by the Helmholtz-Zentrum Berlin für Materialien und Energie. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. The authors acknowledge research funding from the Swedish Research Council (Grant Nos. VR 2016-04590, VR 2018-04125, VR 2018-04330, VR 2018-06465), Swedish Energy Agency (P50626-1, P43549-1), the Göran Gustafsson foundation, the Swedish Foundation for Strategic Research (project nr. RMA15-0130), and the Carl Tryggers foundation (Grant No. CTS 18:59).
| openaire: EC/H2020/730872/EU//CALIPSOplus
PY - 2023/3/8
Y1 - 2023/3/8
N2 - A heterojunction is the key junction for charge extraction in many thin film solar cell technologies. However, the structure and band alignment of the heterojunction in the operating device are often difficult to predict from calculations and, due to the complexity and narrow thickness of the interface, are difficult to measure directly. In this study, we demonstrate a technique for direct measurement of the band alignment and interfacial electric field variations of a fully functional lead halide perovskite solar cell structure under operating conditions using hard X-ray photoelectron spectroscopy (HAXPES). We describe the design considerations required in both the solar cell devices and the measurement setup and show results for the perovskite, hole transport, and gold layers at the back contact of the solar cell. For the investigated design, the HAXPES measurements suggest that 70% of the photovoltage was generated at this back contact, distributed rather equally between the hole transport material/gold interface and the perovskite/hole transport material interface. In addition, we were also able to reconstruct the band alignment at the back contact at equilibrium in the dark and at open circuit under illumination.
AB - A heterojunction is the key junction for charge extraction in many thin film solar cell technologies. However, the structure and band alignment of the heterojunction in the operating device are often difficult to predict from calculations and, due to the complexity and narrow thickness of the interface, are difficult to measure directly. In this study, we demonstrate a technique for direct measurement of the band alignment and interfacial electric field variations of a fully functional lead halide perovskite solar cell structure under operating conditions using hard X-ray photoelectron spectroscopy (HAXPES). We describe the design considerations required in both the solar cell devices and the measurement setup and show results for the perovskite, hole transport, and gold layers at the back contact of the solar cell. For the investigated design, the HAXPES measurements suggest that 70% of the photovoltage was generated at this back contact, distributed rather equally between the hole transport material/gold interface and the perovskite/hole transport material interface. In addition, we were also able to reconstruct the band alignment at the back contact at equilibrium in the dark and at open circuit under illumination.
KW - device design
KW - experimental design
KW - lead halide perovskite
KW - operando measurements
KW - photoelectron spectroscopy
KW - photovoltaics
KW - semiconductor physics
KW - solar cell
UR - http://www.scopus.com/inward/record.url?scp=85149113773&partnerID=8YFLogxK
U2 - 10.1021/acsami.2c17527
DO - 10.1021/acsami.2c17527
M3 - Article
C2 - 36847773
AN - SCOPUS:85149113773
SN - 1944-8244
VL - 15
SP - 12485
EP - 12494
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 9
ER -