Sol–gel synthesis, structural, optical and magnetic characterization of Ag3(2+x)PrxNb4−xO11+δ (0.0 ≤ x ≤ 1.0) nanoparticles

Abstract

In this work we have studied the optical and magnetic properties of sol–gel synthesized nanocrystalline Ag_3(2+x)Pr_xNb_4−xO_11+δ (x = 0.0, 0.50 and 1.0; S1–S3) samples. The structural, morphological, optical and magnetic properties of the nanoparticle were investigated using X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray profile, optical absorbance spectroscopy, vibrating sample magnetometer and electron paramagnetic resonance spectroscopy. The X-ray diffraction results reveal the formation of single-phase monoclinic lattice structure with P2/m in all the samples. The optical absorption spectra indicates charge transfer from O²⁻ to Nb⁵⁺ of niobium and ³H₄ to ¹D₂, ³P₀, ³P₁ and ³P₂ of praseodymium (4f²) ions. Magnetic studies reveal that the samples exhibit ferromagnetism at room temperature. EPR lineshapes of the nanoparticles S1–S3 at 77 and 300 K show a broad unresolved isotropic lineshapes due to the relaxation process.