A research team, led by Prof. Wei Chen and Prof. Zonghao Liu from the Wuhan National Laboratory for Optoelectronics at Huazhong University of Science and Technology (HUST), had their research “An entropy-regulating molecular lock stabilizes formamidinium lead halide perovskite” published in Science on May 15.

FAPbI₃ perovskite solar cells exhibit excellent photovoltaic performance, but the α-phase tends to undergo phase transitions at room temperature, and traditional modification methods fail to fully address its thermodynamic instability. This study reports an entropy-regulating molecular-lock strategy using 1-pyridin-3-ylmethyl-piperazine hydrochloride (3-PMPCl) as a molecular additive to regulate the rotational state of organic cations and suppress the disordered expansion of inorganic octahedra, thereby delaying phase transitions and significantly enhancing the stability of FAPbI₃ perovskite. Perovskite solar cells based on this strategy achieved a certified power conversion efficiency of 27.6% and demonstrated excellent high-temperature operational stability. This work provides a novel technical approach for designing stabilized FAPbI₃ perovskites.

HUST is the primary affiliation for this paper. Master student Tianyin Miao from HUST, Dr. Sanwan Liu from Sungkyunkwan University (SKKU) in South Korea, and Master student Xia Lei from Southern University of Science and Technology are co-first authors of the paper. Prof. Wei Chen, Prof. Zonghao Liu, Prof. Nam-Gyu Park, and Dr. Sanwan Liu from SKKU; Prof. Troshin Pavel from the Federal Research Center for Problems of Chemical Physics and Medicinal Chemistry of Russian Academy of Sciences; and Associate Prof. Jingbai Li from Shenzhen Polytechnic University are the corresponding authors of the paper.

The team has long been dedicated to fundamental and applied research on perovskite solar cells, achieving breakthroughs in the development of large-area, high-efficiency, and high-stability inverted perovskite solar cells and modules, as well as all-perovskite tandem solar cells. The team previously has published papers in Science and Nature Energy and has since conducted systematic research to address key challenges, including stability improvement and large-area module fabrication. The team has achieved consecutive breakthroughs in the study of high-efficiency inverted solar cells, with related findings published in journals such as Science, Nature, Nature Materials, and Nature Energy. Additionally, the team has made notable progress in all-perovskite tandem solar cells, publishing several papers in Nature Communications and Joule.

Source: Wuhan National Laboratory for Optoelectronics, HUST