Spectroscopic ellipsometry and atomic force microscope techniques were employed to analyze optical properties, microstructure and thickness of cobalt oxide thin films deposited on metal substrates by the sol-gel dipping method. The ellipsometric data were conveniently fitted, assuming a stratified structure for the deposited film, which consists of a sublayer native oxide that was coated with a...

Two Cu-Co and Co3O4 oxides were synthesized by the conventional sol-gel auto-combustion and their physical-chemical properties were characterized by XRD, FTIR, SEM, TPR and XPS. The XRD results indicated that copper-cobalt oxide appeared in a mixture form of Cu0.15Co2.85O4 spinel and CuO phases, whereas the cobalt oxide exhibited in the pure form of Co3O4 spinel. The FTIR approved the formation...

sphere-like shaped cobalt oxide nanoparticles (co3o4) were synthesized by a simple wet chemical method using cobalt chloride as precursor and cetyl trimethylammonium bromide (ctab) as surfactant. their structural and surface morphologial properties were characterized by high resolution transmission electron microscopy (hrtem), field emission scanning electron microscopy (fesem) and x-ray diffra...

In this study, mononuclear octahedral cobalt(III) Schiff base complex [CoL3], L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, was synthesized from the reaction of Co(NO3)2•6H2O and the Schiff base ligand L in methanol as solvent. It used as a new precursor to prepare spinel type cobalt oxide nanoparticles by a facile solid-state thermal decomposition. Controlling the temperature and time, Co3...

cobalt oxide (co3o4) nanorods were prepared by a simple co-precipitation method using ethanol solution of cobalt nitrate as precursor and cetyl trimethylammonium bromide (ctab) as surfactant. morphological properties of the nanoparticles were characterized. xrd measurement exhibited the structure of co3o4 nanocrystals for annealed samples. the sem images revealed that the particles changed from...

Artificial photosynthesis is a very attractive and a desirable way to solve the rising energy demand. In order to harvest energy directly from sunlight catalyst for oxygen reduction and evolution reaction are at the core of key renewable-energy technologies including fuel cells and water splitting. Herein, tungsten oxide-reduced graphene oxide (WO3-rGO), cobalt oxidereduced graphene oxide (Co3O...

Cobalt oxide (Co3O4) nanoparticles were successfully prepared by thermal decomposition of cobalt hydroxide synthesized from cobalt acetate, ammonium hydroxide and 10% glycerol. The cobalt oxide nanoparticles calcined at 450 °C were characterized by using XRD. The XRD confirms the crystallinity and crystal structure of the sample. It also shows that the diffraction peak are broadened which revea...

A new concept for preparing hollow metal oxide nanopowders by salt-assisted spray pyrolysis applying nanoscale Kirkendall diffusion is introduced. The composite powders of metal oxide and indecomposable metal salt are prepared by spray pyrolysis. Post-treatment under a reducing atmosphere and subsequent washing using distilled water produce aggregation-free metal nanopowders. The metal nanopowd...

Cobalt oxide films were prepared by electrochemically precipitating the hydroxide and heating it in air to form Co3O4. The resulting oxide films behave as a capacitor. The materials were studied emphasizing their use as either positive or negative electrodes in devices. The capacitance of the material was estimated at different heating temperatures and insight was gained into the charge storage...

We report a facile synthesis of a novel cobalt oxide (Co3O4) hierarchical nanostructure, in which crystalline core-amorphous shell Co3O4 nanoparticles with a bimodal size distribution are uniformly dispersed on ultrathin Co3O4 nanosheets. When tested as anode materials for lithium ion batteries, the as-prepared Co3O4 hierarchical electrodes delivered high lithium storage properties comparing to...