Structural Phase Transition and Magnetic Properties of Nanosized Na-Co-Fe Prussian Blue Analogues
Erdembayalag Batsaikhan1*, Chi-Hung Lee1, Yu-Shuan Huang1, Chu-Yu Tsai1, Wen-Hsien Li1
1Department of Physics, National Central University, Taoyuan, Taiwan
* presenting author:Erdembayalag Batsaikhan,
Prussian Blue analogues (PBAs) have been attracted a particular attention as their alternative applications, due to their three-dimensional open frameworks, simple coprecipitation reaction and intriguing electrochemical and magnetic properties. However, during the conventional rapid precipitation process, large amounts of Fe(CN)6 vacancies was coordinated by water molecules or unexpected impurities, thus leading to the structural instability, reduction of Na content in the lattice as well as decreasing the capacity utilization of PB compounds. Therefore, it is importance to control the crystallization process to fabricate more stable, low-defect and well-defined PB frameworks. It is known that Prussian blue typically crystallizes into a cubic symmetry with the space group Fm-3m, in which transition metal ions are linked together through cyanide (CN) ligands. Depending on the synthesis route, local structural distortion that occurs in the open framework may lead typical cubic to monoclinic, rhombohedral or orthorhombic phase transitions. In this study, we aim to develop a Na-Co-Fe PBA, where it enables to demonstrate structural transition by using the simple co-precipitation routine with low-processing cost at room temperature. As result, increase of nanoparticle size is observed in three distinct Na-Co-Fe. Then, magnetization of nanosized Na-Co-Fe PBAs increases with structural changes.

Keywords: Prussian Blue analogues, structural transition, nanoparticle, magnetization, Curie Weiss behavior