Cobolt-3-oxide;cobalitic oxide

• CAS: 1308-04-9
• Catalog Number: ACM1308049
• Category: Main Products
• Molecular Weight: 165.86
• Molecular Formula: Co2O3
• Synonyms: COBALT(III) OXIDE BLACK
• Appearance: Black powder

Case Study

Comparison of the Catalytic Performance of Different Cobalt Oxides Including Co2O3 in Dye Degradation

Zhang, Botao, et al. Chemical Research in Chinese Universities, 2017, 33, 822-827.

Several different commercial cobalt oxides (CoxOy), including Co2O3, Co3O4 and CoO, were compared for their catalytic performance in dye degradation with activated persulfate (PMS).
Evaluation methods and results
· The catalytic efficiency of cobalt oxides was evaluated using methylene blue (MB), orange G (OG) and eans blue (EB) as target substances. Different cobalt compounds (Co3O4, Co2O3, or CoO) were introduced into their respective solutions to achieve a total cobalt concentration of 0.4 mmol/L, enabling the activation of peroxymonosulfate (PMS). When necessary, a radical scavenger such as 1 mL of methanol or tert-butyl alcohol (TBA) was included. PMS was then added at a concentration of 0.1 mmol to initiate oxidation reactions.
· The results indicated that the dyes were removed swiftly and efficiently in the CoxOy/PMS systems. Among the systems tested, CoO/PMS exhibited the most effective catalytic oxidation of dyes, primarily activating PMS through high levels of soluble cobalt ions. Co3O4 and Co2O3 displayed comparable catalytic activities, activating PMS in a heterogeneous manner with limited soluble cobalt ions, with dye degradation conforming to a pseudo-first-order kinetic model. Additionally, the Co2O3/PMS system showed substantial oxidative performance in a heterogeneous context, presenting an alternative for cobalt-based heterogeneous catalysts in PMS activation oxidation systems.

Preparation of coupled ZnO-Co2O3 and study of its photocatalytic activity

Al-gubury, et al. Journal of Chemical and Pharmaceutical Sciences, 2016, 9(3), 1161-1165.

The coupled ZnO-Co2O3 powder was prepared by directly mixing ZnO and Co2O3 and calcining at 500°C. The ability of the prepared coupled semiconductor to degrade crystal violet dye was then studied to evaluate its photocatalytic activity. The results showed that coupled ZnO-Co2O3 successfully achieved photocatalytic degradation of crystal violet dye, and the optimal conditions were 0.15 gm/100 ml catalyst mass and 5 ppm concentration of crystal violet dye.
Preparation and photocatalytic experiments of coupled ZnO-Co2O3
· Preparation of Mixed Semiconductors: The coupled semiconductors (ZnO-Co2O3) were synthesized using 99.9% pure ZnO and 98% pure Co2O3 powders as the primary materials. These materials were combined using a mortar for one hour, followed by calcination of the mixture at 500ºC for three hours.
· Photoreactor and Procedure: The experiments were conducted in a glass photochemical reactor designed in a cylindrical annular shape, consisting of two sections. The outer section featured a thimble through which running water circulated to cool the reaction solution. This continuous cooling helped maintain the reaction solution at room temperature. The inner section contained the reaction chamber, where a volume of 100 ml of the reaction solution was placed.