Abstract. Lead-free polycrystalline sample of Silver Sodium Niobate (ANN) perovskite ceramics Ag_0.2Na_0.8NbO₃ had been synthesized by solid-state reaction approach for replacing lead-based ceramics. Structural and optical properties of prepared specimen had been investigated corresponding to room temperature. To find crystal structure, X-ray Diffraction (XRD) of powdered sample was done. Lattice parameters as well as the average crystallite size for specimen was determined using XRD data. XRD analysis revealed that synthesized sample of ANN had perovskite orthorhombic structure. Scanning Electron Microscopy (SEM) and the Energy Dispersive X-Ray Spectroscopy (EDX) were used to find microstructural properties. Average grain size of ANN sample was found to be 1.65 μm using Image J Software. Optical properties were studied with the help of Photoluminescence (PL) spectroscopy and Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-VIS DRS).PL spectrum corresponding to excitation wavelength 400 nm had been recorded which showed the presence of visible emissions. Direct band gap was found to be 3.21 eV by Tauc plot. Fourier Transform Infrared (FTIR) spectrum of the sample showed a strong absorption peak at wavenumber 534 cm^-1. This was due to presence of Nb-O bond stretching and Nb-O-Nb bond bending.

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