LiCoPO4 (LCP) exists in three different structural modifications: LCP-Pnma (olivine structure), LCP-Pn21a (KNiPO4 structure type), and LCP-Cmcm (Na2CrO4 structure type). The synthesis of the LCP-Cmcm polymorph has been reported via high[...] Read more.
(LCP) exists in three different structural modifications: LCP-Pnma
(olivine structure), LCP-Pn
structure type), and LCP-Cmcm
structure type). The synthesis of the LCP-Cmcm
polymorph has been reported via high pressure/temperature solid-state methods and by microwave-assisted solvothermal synthesis. Phase transitions from both LCP-Pn
upon heating indicates a metastable behavior. However, a precise study of the structural changes during the heating process and the magnetic properties of LCP-Cmcm
are hitherto unknown. Herein, we present the synthesis and characterization of LCP-Cmcm
via a rapid and facile soft-chemistry approach using two different kinetically controlled pathways, solvothermal and polyol syntheses, both of which only require relatively low temperatures (~200 °C). Additionally, by polyol, method a dumbbell-like morphology is obtained without the use of any additional surfactant or template. A temperature-dependent in situ powder XRD shows a transition from LCP-Cmcm
at room temperature to LCP-Pnma
and finally to LCP-Pn21a
at 575 and 725 °C, respectively. In addition to that, the determination of the magnetic susceptibility as a function of temperature indicates a long-range antiferromagnetic order below TN
= 11 K at 10 kOe and 9.1 K at 25 kOe. The magnetization curves suggests the presence of a metamagnetic transition.