MAS and static NMR study on N–H⋯Br hydrogen bond in organic-inorganic perovskite [NH3(CH2)4NH3]CdBr4 crystal

Abstract

In-depth understanding of the physicochemical properties of organic–inorganic perovskites is essential for their applications in batteries, supercapacitors, and fuel cells. Considering its importance, the physicochemical behavior of [NH3(CH2)4NH3]CdBr4 was analyzed in this study. The crystal structure of the material was found to be monoclinic and the phase transition temperature was determined to be 508 K. The material was thermally stable up to 580 K. Further, the 1H and 13C chemical shifts of the cation, as observed through nuclear magnetic resonance spectroscopy, showed no structural changes with temperature. However, the temperature-dependent 14N chemical shifts of NH3 at both ends of the cation and the 113Cd chemical shifts of the CdBr4 anion indicated the changes in the N–H⋯Br hydrogen bond owing to the change in the structural geometry of CdBr4. The analyzed physicochemical properties revealed critical information regarding the basic mechanisms that will facilitate the broad-scale application of the organic–inorganic perovskite.