A research team headed by Prof. Fang Junfeng from the School of Physics and Electronic Sciences of East China Normal University (ECNU) has achieved breakthrough scientific research in perovskite solar cells.
The achievement was published in Science on January 28, 2022 with the title of “Constructing heterojunctions by surface sulfidation for efficient inverted perovskite solar cells.” ECNU is the first affiliation. Researcher Li Xiaodong is the first author and Prof. Fang Junfeng is the corresponding author.
Researcher Li Xiaodong
A stable perovskite heterojunction was constructed for inverted solar cells through surface sulfidation of lead (Pb)–rich perovskite films. The formed lead-sulfur (Pb-S) bonds upshifted the Fermi level at the perovskite interface and induced an extra back-surface field for electron extraction. The resulting inverted devices exhibited a power conversion efficiency (PCE) >24% with a high open-circuit voltage of 1.19 volts, corresponding to a low voltage loss of 0.36 volts. The strong Pb-S bonds could stabilize perovskite heterojunctions and strengthen underlying perovskite structures that have a similar crystal lattice. Devices with surface sulfidation retained more than 90% of the initial PCE after aging at 85°C for 2200 hours or operating at the maximum power point under continuous illumination for 1000 hours at 55° ± 5°C.
Prof. Fang Junfeng
The research was evaluated by the reviewer of Science as: “novel and impressive”, highest record efficiency in inverted PSCs”, “provided new insight into efficient inverted PSCs”, “greatly promote the further development of inverted PSCs”.
Referring to the application prospects of this research, the research team said, in the future, we will continue to focus on the in-depth research of efficient and stable inverted perovskite batteries, explore new schemes for constructing efficient interface heterojunctions, and further improve the efficiency and stability of devices. At the same time, we will also carry out some research on large-area perovskite battery modules to promote the practical research of perovskite batteries.
Copy editor: Philip Nash
Editor: Li Mengjie