Tuning structural, magnetic, and photocatalytic properties of erbium orthoferrite nanoparticles via co-substitution of Gd3+ and Ti4+

Abstract

Erbium Orthoferrite (ErFeO3) nanoparticles are well-known for magnetic and photocatalysis applications, however the crystallite size will play more crucial role to design for particle applications. Scientists were trying to reduce the crystallite size by adopting different synthetic routes or substitution/co- substitution of appropriate atoms or concentration. In these aspects we prepared the ErFeO3 (EFO) nanoparticle through sol-gel method using EDTA as chelating agent by substitution of isovalent ion (Gd3+) at A-site and higher valence ion (Ti4+) at B-site, i.e., Er1−xGdxFe1−xTixO3 (where x = 0, 2.5, 5 and 7.5 mol%) to tune the chemical and physical properties. The optimized concentration of substitution and co-substitution ion concentration was 5 mol%, which is confirmed through X-ray diffraction (XRD) studies convoyed through structure refinement method (Rietveld). The synthesized samples up to 5 mol% were found to be single phase with orthorhombic crystal structure of space group of Pnma. space group. The scanning electron microscopy (SEM) was utilized to observe the morphology and also calculate the crystallite size the synthesized materials. BET measurements confirm that the synthesized nanomaterials possess a mesoporous structure, with specific surface areas ranging from 15.978 to 41.465 m2/g. The X-ray photoelectron spectroscopy (XPS) analysis was carried out to check the Fe oxidation number and to estimate the oxygen vacancy concentration. Nearly two times higher saturation magnetization (MS) value was observed for 5 mol% substituted and co- substituted sample when compared to un-substituted sample. These results indicate that nanomaterials substituted with 5 mol% Gd and co- substituted with Ti have strong potential for use in gas sensing and photocatalytic applications.