The influence of Mg Substitution at A and B-Sites on the Structural and Optical Properties of LaFeO3 Perovskites
Nova Nur Elisa Dewi(a*), Rahma Maulidia(a), Djoko Triyono(b**), Rifqi Almusawi(b), Iwan Sugihartono(a***)

(a) Program Studi Fisika, FMIPA, Universitas Negeri Jakarta, Jl. Rawamangun Muka, Rawamangun 13220, Indonesia
*nova.elisad[at]gmail.com- ***iwan-sugihartono[at]unj.ac.id

(b) Department of Physics, FMIPA, Universitas Indonesia, Kampus Baru UI, Depok 16424, Indonesia
**djoko.triyono[at]sci.ui.ac.id

Abstract

LaFeO3 with 0.1 Mg substitution at the A-site (La0.9Mg0.1FeO3) and B-site (LaFe0.9Mg0.1O3) has been successfully synthesized via the sol-gel method. The crystal structure, morphology, and optical properties of La0.9Mg0.1FeO3 and LaFe0.9Mg0.1O3 powders were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Ultraviolet-Visible (UV-Vis) Spectroscopy, respectively. Based on the Inorganic Crystal Structure Database (ICSD) No. 98-002-8255, the XRD patterns of both samples possess an orthorhombic structure with Pnma space group. Optically, substituting Mg at both A and B-sites influences the absorbance and reflectance in the wavelength range of 350-800 nm. Moreover, by the Tauc Plot, we have determined the optical band gap of La0.9Mg0.1FeO3 and LaFe0.9Mg0.1O3, which are 1.88 eV and 1.61 eV, respectively.

Keywords: LaFeO3, Mg substitution, A-site and B-site substitution, optical band gap, sol-gel method, perovskite structure

Topic: Material Physics