[SEU News Network, October 29th] (Correspondent Xiong Rengen) Recently, funded by the launch and cultivation fund of “Southeast University’s Top Ten Scientific and Technological Questions”, Shi Pingping, a young teacher from SEU, worked together with the Institute of Science and Applications of Molecular Ferroelectrics, Southeast University & Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, and made great strides in the research of molecular ferroelectrics as she reported the design synthesis of two-dimensional organic-inorganic perovskite ferroelectric semiconductorwith the fluorinated aromatic spacers.
Relevant findings were published on Journal of the American Chemical Society, one of the top journals in the chemical field with the title of “Two-dimensional Organic-Inorganic Perovskite Ferroelectric Semiconductorwith the Fluorinated Aromatic Spacers”
Two-dimensional(2D) organic-inorganic perovskites (OIPs), with improved material stability and structural diversity over the 3D counterparts, offers a rich material platform for relevant functional design regulation and control as well as device application. Researches on this kind of materials mainly focus on the field of high and new technology such as ferroelectrics, solar energy, LED and photodetectors, of which 2D OIP ferroelectric semiconductor is particularly eye-catchingwith its huge potential in the application of multifunctional photoelectric devices. Currently, one of the biggest challenges is to figure out how to effectively introduce a polar structure in a 2D OIP so as to successfully design and modulate ferroelectricity.
The similarities between fluorine and hydrogen atoms in structural parameters such as the Van der Waals radius serve for the maximum maintenance of the original packed structure and crystal symmetry. In the meantime, the strong polarity and larger molecular dipole moment brought by the introduction of maximum electronegativity fluorine atom can also contribute to more polarized unit cell. On that basis, our team adopted the modified strategy of “fluoro effect” to obtain Fluorobenzylamine cations, and then successfully designed and synthesized the 1st two-dimensional organic-inorganic perovskite ferroelectric semiconductorwith the fluorinated aromatic spacers [2-fluorobenzylammonium] 2PbCl4. Its phase-transition temperature reaches 448 K, with bothexceptional ferroelectric properties and semiconductor features. This work provides a reliable method for making two-dimensional organic-inorganic perovskite ferroelectric semiconductor system more diverse and improving the performance and stability of perovskite devices by using more complex conjugated aromatic cations, which wouldlead to more relevant research.
Shi Pingping is this paper’s first author. She is a young teacher at the School of Chemistry and Chemical Engineering of Southeast University.
Provided by: The School of Chemistry and Chemical Engineering
(Editor in charge: Wu Chan Reviewed by: LiXiaonan)