A novel phosphate with CoII square planar coordination, BaCo0.5Fe(PO4)2: structural and magnetic features
Fouad Alloun1, Mohammed Hadouchi1, Sirine El Arni1
1Laboratoire de Chimie Appliquée des Matériaux, Centre des Sciences des Matériaux, Faculty of Science, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, Rabat, Morocco. m.hadouchi@um5r.ac.ma.
Dalton Transactions (Cambridge, England : 2003)
|January 3, 2024
Summary
A new barium, cobalt, and iron phosphate was synthesized and characterized. This novel material exhibits an antiferromagnetic structure below 20 K and a direct bandgap of 2.83 eV.
Area of Science:
- Solid State Chemistry
- Materials Science
- Crystallography
Background:
- Barium, cobalt, and iron phosphates are of interest due to their diverse structural and magnetic properties.
- Understanding the synthesis and characterization of novel phosphate materials is crucial for developing new functional materials.
Purpose of the Study:
- To synthesize and characterize a novel phosphate containing barium, cobalt, and iron.
- To determine the crystal structure, magnetic properties, and optical properties of the synthesized phosphate.
Main Methods:
- Single-crystal X-ray diffraction for structural analysis.
- Sol-gel method for polycrystalline synthesis.
- Scanning electron microscopy (SEM) for morphology and elemental analysis.
- Infrared (IR) and Raman spectroscopy for chemical bonding insights.
- Magnetic susceptibility measurements.
- Optical absorption spectroscopy for bandgap determination.
Main Results:
- The novel phosphate crystallizes in the monoclinic system (space group P21/c) with a 3D framework containing Ba2+ cations in tunnels.
- The polycrystalline form was successfully synthesized via the sol-gel method.
- SEM, IR, and Raman spectroscopy confirmed the material's composition and structure.
- Antiferromagnetic behavior was observed below approximately 20 K.
- A direct bandgap of 2.83 eV was determined.
Conclusions:
- A novel barium cobalt iron phosphate was successfully synthesized and characterized.
- The crystal structure, magnetic, and optical properties were elucidated.
- This material presents potential for applications in magnetism and optoelectronics.
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