Investigation of the Possible Ferroelectric-to-Paraelectric Transition in Bismuth Oxychloride

Ferroelectric materials exhibit ferroelectric characteristics below a specific temperature known as the Curie temperature, even in the absence of an electric field. Above this temperature, these materials display paraelectric properties. This study examined the possible “ferroelectric to paraelectric” transition in BiOCl using the DSC (differential scanning calorimeter) and temperature-dependent Raman spectroscopy. The transition temperature from “ferroelectric to paraelectric” in BiOCl has been determined to be between 355 ºC - 220 ºC. Further, it depends on the thickness of the nanosheets. Additionally, Raman spectroscopy analysis has been carried out on various-thickness nanosheets of BiOCl at ambient temperatures. The obtained results suggest that the Raman active phonon mode peak intensity depends on the thickness of nanosheets. Thicker nanosheets have higher peak (Raman active phonon mode) intensity than thinner nanosheets due to the long-range ordering of atoms.