An investigation on the effect of fuel to oxidizer ratio on the structural properties of (Fe, Mn, Ni, Co, Cr)3O4 high entropy oxide

Subject Areas :

سید عبدالکریم سجادی ¹ (دانشیار، گروه مهندسی متالورژی و مواد، دانشگاه فردوسی مشهد)
azar esmaeilzaei ² (department of materials and metallurgical engineering, ferdowsi university of mashhad)
Jalil Vahdati khaki ³ (Vakil abad Blvd)
sahar mollazadeh ⁴ (department of materials and metallurgical emgineering)

Received: 2023-09-22 Accepted : 2024-09-22

Keywords: High-entropy oxide, Solution combustion synthesis (SCS), Spinel structure,

Abstract :

The main object of this project is to synthesize (Co, Cr, Fe, Mn, Ni)3O4 high entropy oxide through the solution combustion synthesis (SCS) method in the presence of fuel glycine at various fuel to oxidizer (F/O) (0.9, 0.95, and 1) ratios. In order to do that, raw materials were separately dissolved in deionized water and then they were mixed together and heated to a temperature of 330°C using an electric heater. After the water evaporated, a self-sustained exothermic reaction occurred and the porous powders were obtained. X-ray diffraction (XRD) analysis results showed that single-phase (Fe, Mn, Ni, Co, Cr)3O4 oxides with a crystallinity degree of less than 60% at a fuel-to-oxidizer ratio of 0.90 and without any impurities were synthesized by glycine fuel. Additionally, high-resolution transmission electron microscopy (HRTEM) analysis provided evidence for the formation of the desired oxide. Furthermore, inductively coupled plasma (ICP) analysis results indicated the presence of Fe, Co, Ni, Cr, and Mn elements in the synthesized oxide with ratios of 1.0, 0.98, 0.96, 0.94 and 0.95, respectively that verify the chemical composition of the synthesized oxide aligns with the standard chemical composition. Additionally, Raman spectroscopy analysis and elemental surface analysis confirmed the homogeneity of the sample structures.