Abstract
In this work, Ag/AgNbO3−δ composite was prepared by solid-state method. Rietveld refined X-ray diffraction pattern revealed that the sample crystallized in orthorhombic (Pbcm) perovskite structure with small impurities of metallic Ag and confirmed by transmission electron microscopy technique. Fourier transform infrared analysis of this composite indicated the formation of NbO6 octahedral structure. Raman spectroscopy of this composite revealed the suppression of the ferroelectric distortion compared with pure of AgNbO3. X-ray photoelectron spectroscopy results revealed the existence of the Ag1+, Ag0, Nb5+, and O2− states as well as oxygen vacancies in this composite. UV-Vis. analysis revealed that this composite has direct and indirect band gap energies of 3.75 and 1.70 eV, respectively. Differential scanning calorimetry and dielectric measurements of Ag/AgNbO3−δ composite revealed that the phase transitions shifted toward lower temperature compared to pure AgNbO3 perovskite. The polarization-field hysteresis loops of this composite exhibited weak ferroelectric behavior at low electric fields. These results indicated that the lead-free Ag/AgNbO3−δ composite is a promising material for dielectric applications, particularly in dielectric devices.
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This article is derived from a research grant funded by the Research, Development, and Innovation Authority (RDIA) - Kingdom of Saudi Arabia - with grant number (20005-IUM-2023-R-2-1-EI-).
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Abdullah Almohammedi: Investigation, Methodology, Formal analysis, Writing-original draft. E. K. Abdel-Khalek: Investigation, Methodology, Formal analysis, Writing-original draft. Yasser A. M. Ismail: Investigation, Methodology, Writing-original draft.
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Almohammedi, A., Abdel-Khalek, E.K. & Ismail, Y.A.M. Study the influence of the precipitation of metallic Ag on the phase transitions in AgNbO3−δ perovskite. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37405-1
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DOI: https://doi.org/10.1038/s41598-026-37405-1
