Analysis and evaluation of structural properties of Co3O4 microparticles obtained at low temperature

Abstract

In the present research, the synthesis of cobalt oxide Co 3 O 4 was carried out using the sol-gel technique with subsequent heat treatment at 225 and 235 °C. The final product obtained was characterized by X-ray diffraction (XRD), showing a pure crystalline phase of Co 3 O 4 , cell parameters a=b=c=8.071 Å, and a volume of 525.7 Å 3 . The particle size was between 2.37 and 2.77 µm, which indicated that structural transformations from Co to Co 3 O 4 induced an increase in the particle size. Through Rietveld refinement, the interatomic distances and inclination angles of the Co 1 , Co 2 , and Co 3 polyhedra were analyzed in order to establish the structural behavior of cobalt oxide (II, III) at 235 °C. The UV-vis analysis allowed determining band gap (E g ) with values of 1.6 eV in the first region and 0.97 eV in the second. Scanning electron microscopy images showed that the particles agglomerated with increasing calcination temperature and exhibited larger particles. This work presents a detailed analysis of structural parameters of Co 3 O 4 using the Vesta software with Rietveld refinement data.

Co3O4/WO3/C Nanorods with Porous Structures as High-Performance Electrocatalysts for Water Splitting

“…01–074–1657 in positions 2θ of 18.99°, 31.25°, 36.83°, 38.53°, 44.79°, 49.05°, 55.62°, 59.32°, 65.20°, and 68.59°. These physically observed peaks were attributed to the hkl-lattice planes (111), (022), (311), (222), (004), (331), (242), (115), (044), and (153) reflections of Co 3 O 4 with preferential orientation in the plane of 311 as the comparative intensity of PXRD diffraction peaks was used to signify the preferential crystal growth or crystal faceting . Also, the appearance of a broad feature in the major diffraction peaks confirmed the formation of the nanocrystalline CO 3 O 4 sample.…”