Static and dynamic magnetic properties and effect of surface chemistry on the morphology and crystallinity of DyCrO3 nanoplatelets

Abstract

In this contribution, the structural and magnetic properties of DyCrO3 nanoplatelets, synthesized by a hydrolytic sol–gel method, have been investigated. The crystalline phase of DyCrO3 was attained at the decomposition temperature of 800 °C for citric acid and oxalic acid, respectively and their structural analysis indicates a distorted orthorhombic perovskite structure of the DyCrO3 nanoplatelets. The dc-magnetization curve shows the Néel temperature of ∼144 and ∼146 K for DyCrO3 nanoplatelets synthesized using citric acid (DCO (C)) and oxalic acid (DCO (O)), respectively. In addition, DCO (O) shows weak anomalies at ∼22 and ∼6 K in the zero-field-cooled and field-cooled magnetization curves. Below the Néel temperature, DCO (C) and DCO (O) exhibit cross-over from positive to negative magnetization at ∼143 and ∼145 K, respectively. This was attributed to a Dy3+–Cr3+ interaction, which resulted in a weak ferromagnetic coupling (seen as a small opening in the M–H curves). The low temperature transition observed at ∼6 K can be assigned to the onset of Dy3+–Dy3+ antiferromagnetic interaction.