Direct investigation of the reorientational dynamics of A-site cations in 2D organic-inorganic hybrid perovskite by solid-state NMR

• Published in: Nature communications Vol. 13; no. 1; pp. 1513 - 10
• Main Authors: Lin, Cheng-Chieh, Huang, Shing-Jong, Wu, Pei-Hao, Chen, Tzu-Pei, Huang, Chih-Ying, Wang, Ying-Chiao, Chen, Po-Tuan, Radeva, Denitsa, Petrov, Ognyan, Gelev, Vladimir M., Sankar, Raman, Chen, Chia-Chun, Chen, Chun-Wei, Yu, Tsyr-Yan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 21.03.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 140/131; 639/301/299; 639/638/440/94; Ammonium; Cations; Coupling (molecular); Dipole interactions; Dynamic structural analysis; Dynamics; Humanities and Social Sciences; Labeling; multidisciplinary; Nitrogen isotopes; NMR; Nuclear magnetic resonance; Perovskites; Physical properties; Rigidity; Science; Science (multidisciplinary); Solid state; Spacers; Stable isotopes
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-29207-6

Limited methods are available for investigating the reorientational dynamics of A-site cations in two-dimensional organic–inorganic hybrid perovskites (2D OIHPs), which play a pivotal role in determining their physical properties. Here, we describe an approach to study the dynamics of A-site cations using solid-state NMR and stable isotope labelling. 2 H NMR of 2D OIHPs incorporating methyl-d 3 -ammonium cations (d 3 -MA) reveals the existence of multiple modes of reorientational motions of MA. Rotational-echo double resonance (REDOR) NMR of 2D OIHPs incorporating 15 N- and ¹³C-labeled methylammonium cations ( 13 C, 15 N-MA) reflects the averaged dipolar coupling between the C and N nuclei undergoing different modes of motions. Our study reveals the interplay between the A-site cation dynamics and the structural rigidity of the organic spacers, so providing a molecular-level insight into the design of 2D OIHPs. The reorientational dynamics of A-site cations in two-dimensional organic-inorganic hybrid perovskites play an important role in determining their physical properties. Here the authors use solid state NMR and isotope labelling to reveal multiple modes of reorientational motions of methylammonium cations and the role of structural rigidity of the organic spacers on their dynamics.