Ref.: EmaCa32-001

Investigation of the chemical additives on the physical properties of Co3O4 crystals and their application for hydrogen and oxygen evolution reactions

Apresentador: Breno Brito Damasceno

Autores (Instituição): Damasceno, B.B.(Universidade Federal do Ceará); dos Santos, L.P.(Universidade Federal do Ceará); de Vasconcelos, I.F.(Universidade Federal do Ceará);

Resumo:
Due to its physical properties and various applications, Co3O4 has been extensively investigated. Several chemical synthesis routes have been proposed for producing this material, including the use of organic and inorganic chemical agents, which have implications on the morphology and, consequently, on the properties of Co3O4. Therefore, this study investigated the effect of chemical additives in the reaction medium during the hydrothermal synthesis of Co3O4, which included urea, ethylene glycol, glycerol, hydrogen peroxide, sodium borohydride, citric acid, sodium dodecyl sulfate, and cetyltrimethylammonium bromide. The cobalt hexahydrate and the chemical additive were dissolved in a molar ratio of 1:2 in 20 mL of ethanol, aided by an ultrasonic bath, adding 5 mL of ammonia hydroxide, and left for 0.5 hours under constant stirring. Finally, an additional 30 mL of ethyl alcohol was added, and the synthesis was transferred to a Teflon reactor, sealed in an autoclave, and placed in an oven at a temperature of 150°C for 3 hours. The resulting material was characterized by thermogravimetric analysis, X-ray diffraction, ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy, and scanning electron microscopy. In addition to structural, optical, and morphological characterization, the performance of Co3O4 was evaluated for hydrogen and oxygen reactions.